WO2011109605A1 - Thermally resistant reactive silane functional poly-alpha-olefin hot melt adhesive composition, methods of using the same, and solar panel assembly including the same - Google Patents

Thermally resistant reactive silane functional poly-alpha-olefin hot melt adhesive composition, methods of using the same, and solar panel assembly including the same Download PDF

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Publication number
WO2011109605A1
WO2011109605A1 PCT/US2011/027003 US2011027003W WO2011109605A1 WO 2011109605 A1 WO2011109605 A1 WO 2011109605A1 US 2011027003 W US2011027003 W US 2011027003W WO 2011109605 A1 WO2011109605 A1 WO 2011109605A1
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solar panel
thermoplastic
component
adhesive composition
weight
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PCT/US2011/027003
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French (fr)
Inventor
Heidi Hoglund
Kevin Reid
David B. Malcolm
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H.B. Fuller Company
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Publication of WO2011109605A1 publication Critical patent/WO2011109605A1/en

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    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
    • C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
    • C08L23/04—Homopolymers or copolymers of ethene
    • C08L23/08—Copolymers of ethene
    • C08L23/0846—Copolymers of ethene with unsaturated hydrocarbons containing other atoms than carbon or hydrogen atoms
    • C08L23/0892—Copolymers of ethene with unsaturated hydrocarbons containing other atoms than carbon or hydrogen atoms containing monomers with other atoms than carbon, hydrogen or oxygen atoms
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
    • C08G77/00—Macromolecular compounds obtained by reactions forming a linkage containing silicon with or without sulfur, nitrogen, oxygen or carbon in the main chain of the macromolecule
    • C08G77/42—Block-or graft-polymers containing polysiloxane sequences
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J151/00—Adhesives based on graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Adhesives based on derivatives of such polymers
    • C09J151/06—Adhesives based on graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Adhesives based on derivatives of such polymers grafted on to homopolymers or copolymers of aliphatic hydrocarbons containing only one carbon-to-carbon double bond
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
    • H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
    • H01L31/042—PV modules or arrays of single PV cells
    • H01L31/048—Encapsulation of modules
    • H01L31/0481—Encapsulation of modules characterised by the composition of the encapsulation material
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02S—GENERATION OF ELECTRIC POWER BY CONVERSION OF INFRARED RADIATION, VISIBLE LIGHT OR ULTRAVIOLET LIGHT, e.g. USING PHOTOVOLTAIC [PV] MODULES
    • H02S30/00—Structural details of PV modules other than those related to light conversion
    • H02S30/10—Frame structures
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
    • C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2666/00—Composition of polymers characterized by a further compound in the blend, being organic macromolecular compounds, natural resins, waxes or and bituminous materials, non-macromolecular organic substances, inorganic substances or characterized by their function in the composition
    • C08L2666/02—Organic macromolecular compounds, natural resins, waxes or and bituminous materials
    • C08L2666/24—Graft or block copolymers according to groups C08L51/00, C08L53/00 or C08L55/02; Derivatives thereof
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L51/00—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
    • C08L51/06—Compositions of graft polymers in which the grafted component is obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers grafted on to homopolymers or copolymers of aliphatic hydrocarbons containing only one carbon-to-carbon double bond
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L53/00—Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/50—Photovoltaic [PV] energy

Definitions

  • the invention is directed to maintaining adhesion between two substrates under challenging environmental conditions.
  • Solar panels and solar panel fields have unique requirements in that they must maintain their integrity under conditions of high humidity, because they are often positioned out doors and exposed to rain, freezing rain, and snow, and under conditions of widely varying temperature extremes because they are often positioned in hot deserts, on hot asphalt rooftops, and in climates that experience extremely high temperatures, extremely low temperatures, and strong winds.
  • any mechanism used to secure and maintain solar panels in a fixed position must function under a difficult set of environmental conditions.
  • the invention features a moisture curable adhesive composition that includes a silane functional poly-a-olefin polymer; a thermoplastic component having a softening point of at least 120°C and selected from the group consisting of thennoplastic elastomers, thermoplastic polymers, and combinations thereof; a silane adhesion promoter having a flash point greater than 100°C at atmospheric pressure and a boiling point greater than 100°C at from 0.5 mmHg (millimeters of mercury) to 15 mmHg; and optionally, a thermoplastic tackifying agent having a softening point greater than 80°C, and optionally a thennoplastic component having a softening point of lower than 120°C and selected from the group consisting of thermoplastic elastomers, thermoplastic polymers, and combinations thereof.
  • the adhesive composition includes a silane functional poly-a- olefin polymer having a softening point of at least 120°C; a silane adhesion promoter having a flash point greater than 100°C at atmospheric pressure and a boiling point greater than 100°C at from 0.5 mmHg (millimeters of mercury) to 15 mmHg; optionally, a thermoplastic tackifying agent having a softening point greater than 80°C; and optionally, a thermoplastic component having a softening point of lower than 120°C and selected from the group consisting of thermoplastic elastomers, thermoplastic polymers, and combinations thereof.
  • the adhesive composition includes from about 5 % by weight to about 80 % by weight of the silane functional amorphous poly-a-olefin polymer; and from about 5 % by weight to about 35 % by weight of the thermoplastic tackifying agent.
  • the adhesive composition exhibits an initial lap shear of at least 1 psi at 23 °C.
  • the adhesive composition further includes a spacer in a form of spheres, cylinders, tubes, strips, ropes, or any other suitable forms.
  • the invention features a solar panel assembly that includes a solar panel, a support, and a moisture curable adhesive composition disclosed herein, the support being bonded to the solar panel through the adhesive composition.
  • the solar panel includes a substrate that includes glass, and a superstate, the adhesive
  • the solar panel includes a substrate that includes polymer, and the adhesive composition is in contact with the polymer of the substrate.
  • the support is metal.
  • the support remains bonded to the substrate of the solar panel through the adhesive composition after undergoing the at least one of the Simulated Aging Tests set forth in UL 1703 and the tests set forth in IEC 6646.
  • the invention features a method of adhering a component of a solar panel assembly to a solar panel, the method including contacting at least one of a first component and a second component with an adhesive composition disclosed herein, the first component including a component of the solar panel assembly other than the solar panel, and the second component including the solar panel, and allowing the adhesive composition to cure to bond the first component to the second component
  • the first component includes at least one of a back rail, a frame and a junction box
  • the second component includes a substrate of the solar panel, the substrate including at least one of polymer and glass.
  • the first component includes a metal back rail and the second component includes a substrate of the solar panel, the substrate including at least one of polymer and glass.
  • the adhesive composition exhibits good green strength, an ability to be handled shortly after application (e.g., an assembly that includes the adhesive composition can be handled shortly after application of the adhesive composition thereto), and, when cured, good durability in a wide range of environmental conditions.
  • the adhesive composition can also be applied using an automated process.
  • FIG. 1 is a plane view a back rail of a solar panel assembly bonded to a substrate of a solar panel through an adhesive composition disclosed herein.
  • FIG. 2 is a plane view of a junction box of a solar panel assembly bonded to a substrate of a solar panel through an adhesive composition disclosed herein.
  • FIG. 3 is a plane view of an end bracket of a solar panel assembly bonded to a solar panel through an adhesive composition disclosed herein.
  • FIG. 4 is a perspective view of a framed solar panel assembly.
  • FIG. 5 is view taken in cross section along line A-A of the framed solar panel assembly of FIG. 4.
  • FIG. 6 is a perspective view of a solar panel.
  • FIG. 7 is an enlarged view of a portion of a framed solar panel assembly with an adhesive/sealant composition configured according to another embodiment.
  • the moisture curable hot melt adhesive composition includes a silane functional poly-a-olefin polymer, a thermoplastic component having a softening point of at least 120°C, and a silane adhesion promoter having a flash point greater than 100°C at atmospheric pressure and a boiling point greater than 100°C at from 0.5 mmHg to 15 mmHg.
  • the adhesive composition cures upon exposure to atmospheric moisture to a composition that exhibits a tensile strength of at least 20 psi at 23 °C, or even at least 70 psi at 23 °C, and at least 20 psi at 85°C, or even at least 70 psi at 85°C.
  • the adhesive composition preferably exhibits an initial lap shear strength (i.e., green strength) of at least 1 psi, at least 2 psi, or even at least 4 psi at 23°C, and a final lap shear of at least 1 psi, at least 2 psi, or even at least 4 psi at 85°C.
  • the adhesive composition also exhibits cold temperature flexibility.
  • the adhesive composition is creep resistant and preferably passes the creep resistance test method at 85°C, or even at a higher temperature than 85°C.
  • Solar panel assemblies that include the cured adhesive composition preferably pass the Simulated Aging Tests set forth in UL 1703, or even the tests of IEC 6646.
  • the cured adhesive composition preferably maintains a support bonded to a solar panel after undergoing the Simulated Aging Tests set forth in UL 1703, or even the tests of IEC 6646.
  • Particularly useful silane functional poly-a-olefin polymers are either completely amorphous or have a low level of crystal linity.
  • the degree of crystallinity preferably is no greater than 25 % as determined by X-ray diffraction.
  • Useful silane functional amorphous poly-a-olefin polymers are derived by grafting amorphous poly-a-olefin and a silane source.
  • Suitable amorphous poly-a-olefins include, e.g., homopolymers, copolymers and terpolymers including, e.g., atactic polypropylene, atactic poly-l-butene and combinations thereof.
  • the amorphous poly-a-olefins can be random or block copolymers.
  • Other suitable amorphous poly-a-olefin polymers include, e.g., homogeneous substantially linear ethylene-a-olefin interpolymers of monomers including, e.g., propylene, 1 -butene, 1-pentene, 3-metyI-l -butene, 1-hexene, 3-methyl-l -pentene, 4-methyl-l-pentene, 3 -ethyl- 1 -pentene, 1 -octene, 1-decene, and 1 -undecene; amorphous copolymers with other olefins (e.g., ethylene, 1 -butene, 1- pentene, 1 -hexene, 4-methyl- 1 -pentene, 1 -octene, and 1-decene) containing propylene as a main component,
  • One example of a useful class of amorphous poly-a-olefins include copolymers and terpolymers derived from 0 % by weight to 95 % by weight a-olefms having from 4 to 10 carbon atoms, (in other embodiments from 3 % by weight to 95 % by weight), from 5 % by weight to 100 % by weight propane (in other embodiments from 5 % by weight to 97 % by weight), and from 0 % by weight to 20 % by weight ethane as described, e.g., in U.S. Patent No. 5,994,474 and incorporated herein.
  • the silane to be grafted on the amorphous poly-a-olefin can have two or three alkoxy groups attached directly to the silicon and at least one olefmic double bond containing moiety.
  • Suitable examples include vinyltrimethoxysilane, vinyltriethoxysilane, vinyl tris(2- methoxyethoxy)silane, 3-methacryloxypropyltrimethoxysilane, 3- methacryloxypropyltriethoxysilane, vinyldimethylmethoxysilane and
  • the amount silane for grafting on the amorphous poly-a-olefin is from about 0.1 % by weight to about 10 % by weight, from about 2 % by weight to about 6 % by weight, or even from about 3 % by weight to about 5 % by weight, based on the amorphous poly-a-olefin.
  • Any known method for grafting silane onto the amorphous poly-a-olefin can be used including, e.g., solution and melt (e.g., using an appropriate amount of a free-radical donor) methods.
  • Useful methods of preparing silylated amorphous poly-a-olefin are described, e.g., in U.S. 5,994,474 and DE 40 00 695 and incorporated herein.
  • free- radical donors include diacyl peroxides such as dilauryl peroxide and didecanoyl peroxide, alkyl peresters such as tert-butyl peroxy-2-ethylhexanoate, perketals such as l ,l -di(tert- butylperoxy)-3,3, 5-trimethylcyclohexane or l,l-di(tert-butylperoxy)cycIohexane, dialkyl peroxides such as tert-butyl cumyl peroxide, di(tert-butyl) peroxide and dicumyl peroxide, C- radical donors including, e.g., 3,4-dimethyl-3,4-diphenylhexane and 2, 3 -dim ethyl -2, 3- diphenylbutane, and azo compounds (e.g., 2,2'-azodi(2-acetoxypropane)).
  • the amorphous poly-a-olefin has a number average molecular weight (Mn) from about 7,000 to about 14,000, a weight average molecular weight (Mw) from about 35,000 to about 90,000 and a Z average molecular weight (Mz) from about 13,000 to about 33,000, and polydispersity (MWD) from about 4.9 to about 6.2.
  • Mn number average molecular weight
  • Mw weight average molecular weight
  • Mz Z average molecular weight
  • Mz polydispersity
  • Preferred silane functional amorphous poly-a-olefin polymers include the silane functional amorphous poly-a-olefin polymers that are commercially available under the VESTOPLAST trade designation from Evonik, Germany including, e.g., VESTOPLAST 206V silane functional amorphous poly-a-olefins.
  • the silane functional poly-a-olefm polymer has a softening point of less than 120°C. in one embodiment, the silane functional poly-a-olefm polymer has a softening point of at least 120°C.
  • the silane functional poly-a-olefm polymer is present in the composition in an amount of from about 5 % by weight to about 80 % by weight, from about 15 % by weight to about 50 % by weight, or even from about 25 % by weight to about 40 % by weight, based on the weight of the composition.
  • the thermoplastic component has a softening point of at least 120°C and includes a thermoplastic elastomer that has a softening point of at least 120°C, a thermoplastic polymer that has a softening point of at least 120°C, or a combination thereof.
  • the thermoplastic component having a softening point of at least 120°C is present in the adhesive composition in an amount of from about 10 % by weight to about 75 % by weight, from about 20 % by weight to about 70 % by weight, or even from about 40 % by weight to about 60 % by weight, based on the weight of the composition.
  • the thermoplastic component having a softening point of at least 120°C may or may not be present in the adhesive composition.
  • Suitable thermoplastic elastomers having a softening point of at least 120°C include, e.g., polyetheramide block copolymers, polyesters, butadiene-styrene elastomers including, e.g., A-B, A-B-A, A-(B-A)n-B, (A-B)n-Y, and radial block copolymers and grafted versions thereof where the A block(s) is a polyvinyl aromatic block (e.g., styrene), and the B block is a rubbery midblock (e.g., isoprene, butadiene, efhylene-butylene, and ethylene-propylene) (e.g., styrene-butadiene-styrene block copolymers, styrene-isoprene-styrene block copolymers, styrene-ethylene-butylene-st
  • thermoplastic elastomers having a softening point of at least 120°C include, e.g., thermoplastic elastomers available under the HYTREL 3078, HYTREL 4053 and HYTREL 4056 trade designations from E.I. DuPont de Nemours
  • styrene-ethylene/butylene-styrene block copolymers available under the KR ATON G series of trade designations including, e.g., KRATON G-1652 and G- 1657, from Kraton Polymers (Houston, Texas); styrene-butadiene-styrene and styrene- isoprene-styrene block copolymers available under the KRATON D series of trade
  • KRATON D-l 1 1 1 and D-l 112 from Kraton Polymers
  • silane terminated block copolymers available under the KRATON SKFGIOI trade designation from Kraton Polymers
  • styrene-butadiene-styrene and styrene-isoprene-styrene block copolymers available under the VECTOR series of trade designations including, e.g.,
  • VECTOR 41 12, 41 14 and 441 1 from Dexco Polymers (Houston, Texas); ethylene-octene block copolymers available under the INSITE trade designation including e.g., 1NSITE D9807.15 from Dow Chemical Company.
  • thermoplastic elastomer having a softening point of at least 120°C can be present in the adhesive composition in an amount of 0 % by weight, or from about 10 % by weight, or from about 20% by weight to about 75% by weight, or to about 60 % by weight, or to about 40 % by weight, based on the weight of the composition.
  • thermoplastic polymers having a softening point of at least 120°C can be selected from a variety of classes of thermoplastic polymers including, e.g., polyalkylenes (e.g., polyethylene, polypropylene and polybutylene), poly(alpha)olefins including, e.g., homo-, co- and terpolymers of aliphatic mono- 1 -olefins (alpha olefins) (e.g., poly(alpha)olefms containing from 2 to 10 carbon atoms), homogeneous linear or substantially linear
  • polyalkylenes e.g., polyethylene, polypropylene and polybutylene
  • poly(alpha)olefins including, e.g., homo-, co- and terpolymers of aliphatic mono- 1 -olefins (alpha olefins) (e.g., poly(alpha)olefms containing from 2 to
  • polyethylene terephthalate polyacrylates, polymethacrylates, polyacrylamides,
  • polyacrylonitriles copolymers of acrylonitrile and monomers including, e.g., butadiene, styrene, polymethyl pentene, and polyphenylene sulfide (e.g., styrene-acrylonitrile, acrylonitrile-butadiene-styrene, acrylonitrile-styrene-butadiene rubbers), polyimides, polyamides, copolymers of vinyl alcohol and ethylenically unsaturated monomers, polyvinyl acetate (e.g., ethylene vinyl acetate), polyvinyl alcohol, vinyl chloride homopolymers and copolymers (e.g., polyvinyl chloride), terpolymers of ethylene, carbon monoxide and acrylic acid ester or vinyl monomer, polysiloxanes, polyuremanes, polystyrene, and combinations thereof, and homopolymers, copolymers and terpolymers thereof,
  • thermoplastic polymers having a softening point of at least 120°C include, e.g., amorphous polyalphaolefins available from Evonik under the trade designations VESTOPLAST 308, VESTOPLAST 608, and VESTOPLAST 703, atactic polypropylene polymers available under the REXTAC series of trade designations including, e.g., REXTAC RT 2535 and RT 2585, from REXtac LLC (Odessa, Texas) and the
  • EASTOFLEX series of trade designations including, e.g., EASTOFLEX El 060, from
  • thermoplastic polymer having a softening point of at least 120°C is preferably present in the adhesive composition in an amount of 0 % by weight, or from about 10 % by weight, or from about 20% by weight to about 75% by weight, or to about 60 % by weight, or to about 40 % by weight, based on the weight of the composition.
  • the adhesive composition also includes a silane adhesion promoter that has a flash point greater than 100°C at atmospheric pressure and a boiling point greater than 100°C at from 0.5 mmHg to 15 mmHg.
  • Silane adhesion promoters are compounds or monomers that have an average molecular weight of from about 300 to about 1000, or from about 300 to about 800, or from about 500 to about 700.
  • Useful silane adhesion promoters include silyl groups such as alkoxysilyls, acryloxysilyls, alkyloxyiminosilyls, oxime silyls, amino silyls, and combinations thereof.
  • alkoxysilyl groups include methoxysilyl, ethoxysilyl, propoxysilyl, butoxysilyl, and acyloxysilyl reactive groups including, e.g., silyl ester of various acids including, e.g., acetic acid, 2-ethylhexanoic acid, palmitic acid, stearic acid, and oleic acid.
  • Suitable silane adhesion promoters include, e.g., methacryloxy propyl triethoxy-silane, M-aminophenyltriethoxy-silane, P-aminophenyltriethoxy-silane, N-(2-aminoethyl)-3- aminopropyl triethoxy-silane, n-butylaminopropyltrimethoxy-silane,
  • silane adhesion promoters are commercially available under the SILQUEST A-l 170 and SILQUEST SILQUEST A-LINK 597 trade designations from Momentive Performance Materials, Inc. (Albany, New York).
  • the silane adhesion promoter is preferably present in the composition in an amount of from about 0.01 % by weight to about 5 % by weight, from about 0.01 % by weight to about 2 % by weight, or even from about 0.01 % by weight to about 1 % by weight, based on the weight of the composition.
  • the adhesive composition may also include other optional ingredients e.g., a thermoplastic component having a soften point of less than 120°C, a thermoplastic tackifying agent having a ring and ball softening point of at least 80°C, and combinations thereof.
  • a thermoplastic component having a soften point of less than 120°C e.g., a thermoplastic tackifying agent having a ring and ball softening point of at least 80°C, and combinations thereof.
  • Useful thermoplastic components having a soften point of less than 120°C include such as thermoplastic elastomers having a soften point of less than 120°C, thermoplastic polymers having a soften point of less than 120°C, and combinations thereof. Examples of useful thermoplastic components include all the classes of the thermoplastic components listed above.
  • thermoplastic elastomers having a soften point of less than 120°C include e.g., polyisobutylene, butyl rubber, ethylene/propylene/diene rubber (i.e., EPDM rubber), and combinations thereof.
  • thermoplastic elastomers having a soften point of less than 120°C include e.g., polyisobutylenes available under the OPPANOL series of trade designations including B50, B80, B100, B 150, B200, B246, B12 and B15 trade designation from BASF (Germany); polyisobutylenes available under the VISTANEX series of trade designations from ExxonMobil including VISTANEX LMMS, MML-80, MML-100, MML-120, and MML 140; isobutylene-isoprene copolymers available the BUTYL Rubber series of trade designations including BUTYL 268 and BUTYL 065 from ExxonMobil Chemical Co. (Houston, Texas); ethylene-propylene copolymers available under the VISTALON series of trade designations including, e.g., V1STALON 404, from ExxonMobil Chemical Co.
  • thermoplastic polymers having a soften point of less than 120°C include e.g., ethylene vinyl acetate copolymers available under the ATEVA series of trade designations from AT Plastics ( Brampton, Ontario, Canada) including ATEVA 4030MC and ATEVA 1850, the ELVAX series of trade designations from DuPont de Nemours (Wilmington, Delaware) and the ULTRATHENE series of trade designations from Millennium Petrochemicals (Rolling Meadows, Illinois); ethylene n-butyl acrylate copolymers available under the LOTRYL series of trade designations from Elf Atochem North America (Philadelphia, Pennsylvania), the ESCORENE series of trade designations from ExxonMobil Chemical Co. and the EN ATHENE series of trade
  • thermoplastic polyurethane polymers available under the PEARLSTICK series of trade designations from Aries Technologies (Derry, New Hampshire a distributor for Merquinsa,
  • ethylene acrylate copolymers also available under the ELVALOY series of trade designations from DuPont; and acrylic polymers available under the ELVACITE series of trade designations from ICI Acrylics (St. Louis, Missouri); useful commercially available homogeneous linear or substantially linear interpolymers of ethylene having at least one C 3 to C?o alpha olefin and a polydispersity less than about 2.5 include, e.g., EXACT 5008 ethylene- butene copolymer, EXXPOL SLP-0394 ethylene-propylene copolymer, and EXACT 3031 an ethylene-hexene copolymer from ExxonMobil Chemical Co. (Houston, Texas) and ethylene/1. -octene polymers available under the trade designation AFFINITY from Dow Chemical Co. (Midland, Michigan).
  • thermoplastic component having a softening point of less than 120°C is preferably present in the adhesive composition in an amount of from 0 % by weight, to about 20 % by weight, based on the total weight of the composition.
  • thermoplastic tackifying agents have a ring and ball softening point of at least 80°C, or even from about 85°C to about 150°C.
  • the tackifying agent preferably is free of groups with which the silanol group of the silyated amorphous poly-a-olefm will react.
  • Suitable tackifying agents include aliphatic, cycloaliphatic, aromatic, aliphatic- aromatic, aromatic modified alicyclic, and alicyclic hydrocarbon resins and modified versions and hydrogenated derivatives thereof; terpenes (polyterpenes), styrenated teipenes, modified terpenes (e.g., phenolic modified terpene resins), hydrogenated derivatives thereof, and combinations thereof; alpha methyl styrene resins and hydrogenated derivatives thereof; and combinations thereof.
  • Other useful tackifying agents are disclosed in. e.g., U.S. Patent No. 6,355,317, and incorporated herein.
  • tackifying agents include natural and modified rosins such as gum rosin, wood rosin, tall oil rosin, distilled rosin, completely or partially hydrogenated rosin, dimerized rosin and polymerized rosin; rosin esters including, e.g., glycerol and pentaerythritol esters of natural and modified rosins, (e.g., glycerol esters of pale, wood rosin, glycerol esters of hydrogenated rosin, glycerol esters of polymerized rosin, pentaerythritol esters of
  • Suitable commercially available tackifying agents include, e.g., cycloaliphatic hydrocarbon resins and aromatic-modified, cycloaliphatic hydrocarbon resins available under the ESCOREZ 5637 and ESCOREZ 5340 trade designations from Exxon Mobile Chemical Company; partially hydrogenated cycloaliphatic petroleum hydrocarbon resins available under the EASTOTAC series of trade designations (e.g., EASTOTAC H-130 and H-142) from Eastman Chemical Co. (Kingsport, Tennessee) available in grades E, R, L and W, which have differing levels of hydrogenation from least hydrogenated (E) to most hydrogenated (W), the ESCOREZ series of trade designations including, e.g., ESCOREZ 5320 and
  • HERCOLITE 2100 trade designation from Eastman Chemical Co. partially hydrogenated aromatic modified petroleum hydrocarbon resins available under the ESCOREZ 5600 trade designation from ExxonMobil Chemical Co.; aromatic hydrogenated hydrocarbon resins available under the trade designation REGALREZ 1 126 and alphamethyl styrene resins available under the trade designation KRISTALEX 5140 from Eastman Chemical Co.
  • the tackifying agent is preferably present in the composition in an amount of from about 0 % by weight, or from about 5 % by weight to about 15 % by weight, or to about 20 % by weight, or to about 35 % by weight, based on the weight of the composition.
  • the adhesive composition may also include other additives including, e.g., fillers, waxes, plasticizers, thermal stabilizers, light stabilizers (e.g., UV light stabilizers and absorbers), optical brighten ers, antistats, lubricants, antioxidants, catalysts, rheology modifiers, biocides, corrosion inhibitors, dehydrators, organic solvents, colorants (e.g., pigments and dyes), surfactants antiblocking agents, nucleating agents, flame retardants and combinations thereof.
  • additives including, e.g., fillers, waxes, plasticizers, thermal stabilizers, light stabilizers (e.g., UV light stabilizers and absorbers), optical brighten ers, antistats, lubricants, antioxidants, catalysts, rheology modifiers, biocides, corrosion inhibitors, dehydrators, organic solvents, colorants (e.g., pigments and dyes), surfactants antiblocking agents, nucleating agents, flame retardants and combinations thereof
  • Suitable fillers include, e.g., fumed silica, precipitated silica, talc, calcium carbonates, carbon black, alumina silicates, clay, zeolites, ceramics, mica, titanium dioxide, and combinations thereof.
  • the composition can include filler in an amount of from 0 % by weight to about 40 % by weight, from about 10 % by weight to about 35 % by weight, or even from about 20 % by weight to about 30 % by weight, based on the weight of the composition.
  • the plasticizer preferably has a boiling point of greater than about 85°C.
  • Preferred plasticizers include paraffinic oils, naphthenic oils, low molecular weight poly- 1 -but ene, low molecular weight polyisobutene, and combinations thereof Plasticizer can be present in the composition in an amount of from 0 % by weight to about 10 % by weight, based on the weight of the composition.
  • a crosslinking accelerator can be added to the composition to increase the rate of crosslinking.
  • Useful crosslinking accelerators include, e.g., organotin compounds including, e.g., dialkyl tin dicarboxylates (e.g., dibutyl tin dilaurate and dibutyl tin diacetate), tin carboxylates, tertiary amines, stannous salts of carboxylic acids, e.g., stannous octoate and stannous acetate, tetrabutyl dioleatodistannoxane, titanium compounds, organosilicon titantates, alkyltitantates, and metal alkoxides (e.g., aluminum isopropoxide and zirconium isopropoxide), and combinations thereof.
  • organotin compounds including, e.g., dialkyl tin dicarboxylates (e.g., dibutyl tin
  • the accelerator can be added either in pure form or, for greater ease of metering, in the form of a master batch that includes the amorphous poly- a-olefm.
  • the accelerator can be added to the composition before melting, in the form of a dry mix, or after melting. Accelerator preferably is present in amounts from 0.001 % by weight to 5 % by weight, or even from 0.01 % by weight to 1 % by weight, based on the weight of the composition.
  • the adhesive composition is useful for bonding a variety of substrates to each other including substrates made from, e.g., glass, polymer (e.g., polymer composites), metal (e.g., stainless steel, aluminum (e.g., anodized aluminum), galvanized steel and cold-rolled steel), and combinations thereof, treated and coated substrates (e.g., substrates treated for corrosion resistance, aluminum and zinc coated substrates, and combinations thereof), painted substrates and combinations thereof.
  • substrates made from, e.g., glass, polymer (e.g., polymer composites), metal (e.g., stainless steel, aluminum (e.g., anodized aluminum), galvanized steel and cold-rolled steel), and combinations thereof, treated and coated substrates (e.g., substrates treated for corrosion resistance, aluminum and zinc coated substrates, and combinations thereof), painted substrates and combinations thereof.
  • substrates made from, e.g., glass, polymer (e.g., polymer composites), metal (e.g., stainless
  • the adhesive composition is useful for bonding the various components of a solar panel assembly to each other including such components as, e.g., solar panel frames (e.g., C- shaped channels), junction boxes (e.g., polymeric junction boxes), back rails for supporting solar panels (e.g., metal back rails), , brackets (e.g., end brackets), solar panels, components of solar panels (e.g., superstrate, substrate and edges), components used in mounting the solar panels, components used in supporting the solar panels, and combinations thereof.
  • Useful solar panel superstrates include a layer of an ultra violet light transparent material (e.g., glass), and useful solar panel substrates include a layer of polymer, polymer composite, and combinations thereof.
  • the aforesaid adhesive composition is particularly used for sealing and mounting frames on a solar panel to form a framed solar panel assembly.
  • Solar panels are often surrounded by a frame and adhered to the frame with a structural adhesive. It is often necessary to include both a structural adhesive and a moisture vapor barrier to achieve a framed solar panel that will maintain its integrity under the rigorous conditions to which it is often exposed including, e.g., high humidity, widely varying temperature extremes, and strong winds.
  • the aforesaid adhesive composition can function as both an adhesive and a moisture vapor barrier, therefore, is referred to as an adhesive/sealant composition.
  • the adhesive/sealant composition exhibits a moisture vapor transmission rate (MVTR) of no greater than 2 g/m 2 /day.
  • the adhesive/sealant composition exhibits a MVTR of no greater than 1 g/m /day.
  • the adhesive/sealant composition exhibits a MVTR of no greater than 0.2 g/m 2 /day.
  • the invention provides a framed solar panel assembly.
  • the solar panel assembly includes a solar panel that includes edges; a peripheral frame including an interior surface; and any one of the aforesaid adhesive/sealant compositions disposed between the interior surface of the frame and the edges of the solar panel, the panel being bonded to the frame through the adhesive/sealant composition.
  • the invention provides a method of framing a solar panel.
  • the method includes contacting at least one of the interior surfaces of a frame and the solar panel with any one of the adhesive/sealant compositions disclosed herein, and affixing the frame to the solar panel.
  • the method further includes allowing the adhesive/sealant composition to cure such that the frame is bonded to the solar panel through the cured adhesive/sealant composition.
  • the framed solar panel assemblies exhibit good protection against moisture, which can adversely affect the efficiency of the solar panel.
  • the method provides an efficient framing process and enables the manufacture of a framed solar panel assembly using an adhesive/sealant composition that functions as both an adhesive composition and a sealant composition at the same time, especially as an edge sealant composition.
  • a back rail 10 of a solar panel assembly 5 is bonded to a substrate 8 of a solar panel 12 through an adhesive composition 6.
  • FIG. 2 illustrates a junction box 20 bonded to a substrate 8 of a solar panel 12 through an adhesive composition 6.
  • an end bracket 30 is bonded to an edge 22, substrate 8 and superstrate 24 of a solar panel 12 through an adhesive composition 6.
  • FIGS. 4-6 illustrate a framed solar panel assembly 1 1 includes a solar panel 12 and a peripheral frame 14.
  • the solar panel 12 is surrounded by the frame 14 along edges 16, 18, 20, and 22.
  • An adhesive/sealant composition 4 is disposed between the edges 16, 18, 20 and 22 and the interior surface 28 of the frame 14 so as to seal the solar panel 12, which provides a barrier to moisture entering the solar panel 12, and to adhere the frame 14 to the edges 16, 18, 20 and 22 of the solar panel 12.
  • a continuous bead of the adhesive/sealant composition 4 is in continuous contact with the edge of the solar panel 12 to form a vapor barrier.
  • the frame 14 defines a U-shaped channel 32 that receives an edge of the solar panel 12.
  • the channel 32 includes a back wall 34, a top wall 36, and a bottom wall 38.
  • the adhesive/sealant composition 4 is in contact with at least one component of the channel 32 of the frame 14, e.g., the back wall 34, a top wall 36, and a bottom wall 38 of the frame 14, and at least one component of the solar panel 12, e.g., the edges 16, 18, 20, and 22 of the panel 12, the superstrate 24 (e.g., a glass superstrate) of the solar panel 12, and the substrate 8 (e.g., a polymer substrate or a glass substrate) of the solar panel 12, as shown in FIG. 6.
  • the adhesive/sealant composition 4 is positioned in a discontinuous manner on the bottom wall 38, back wall 34, and top wall 36 of the channel 32 of the frame 14 that receives the solar panel 12.
  • the adhesive/sealant composition 4 bonds the frame 14 to the solar panel 12 and preferably provides a vapor barrier.
  • the adhesive/sealant composition 4 preferably exhibits a moisture vapor transmission rate (MVTR) of no gi'eater than 2 g/m 2 /day, when in the form of a 60 mil film.
  • solar panel assemblies in which the adhesive composition is particularly useful include those constructions described in, e.g., U.S. 2009/0205703 and U.S. 2010/0018570, which are incorporated herein.
  • Test procedures used in the examples include the following.
  • the tensile strength at break is determined according to ASTM-D638-00 entitled, "Standard Test Method for Tensile Properties of Plastics.”
  • ASTM-D638-00 entitled, "Standard Test Method for Tensile Properties of Plastics.”
  • a homogeneous film of the adhesive composition is pressed to a thickness of from 40 mil to 60 mil.
  • the film is conditioned at 23 °C and 50 % relative humidity for 12 weeks to cure. Specimens are cut from the film and tested for tensile strength at break according to ASTM D638-00.
  • the lap shear strength is determined according to ASTM C-961-01 entitled. "Standard Test Method for Lap Shear Strength of Hot Applied Sealants, " with the exception that the test specimen is prepared as follows. A 1 in x 1 in film of adhesive composition having a thickness of from 50 mil to 60 mil is placed on a 4 in x 1 in piece of a first substrate (stainless steel). A 1 in x 3 in piece of a second substrate ⁇ stainless steel) is then placed on top of the film and pressed hard against the film using maximum hand pressure. The test specimen is then heated to a temperature of from 120°C-150°C for 10 minutes to achieve good wet out of the adhesive composition.
  • Initial lap shear i.e., green strength
  • Final lap shear is measured 12 weeks after preparing the bond sample.
  • Creep resistance is determined as follows. A 1 in x 1 in film of adhesive composition having a thickness of from 50 mil to 60 mil is placed on a 4 in x 1 in piece of aluminum. A 1 in x 3 in piece of glass is then placed on top of the film and pressed hard against the film using maximum hand pressure. The test specimen is then heated to a temperature of from 120°C to 150°C for 10 minutes to achieve good wet out of the adhesive composition. The test specimen is allowed to cure for at least 4 weeks.
  • a one pound load is then hung from an end of the test specimen and placed in an oven at a specified temperature, e.g., at 85 °C or even a higher temperature. The time to failure is recorded. The test specimen is recorded as pass at the test temperature if there is no failure after seven days.
  • Moisture curable hot melt adhesive compositions of Examples 1 and 2 are prepared according to Table I by mixing all thermoplastic polymer(s), polyols, and tackifier (if added) in a molten state until uniformly blended. The silane tenninated APAO is then added and mixed under vacuum for 1 -3 hours. Catalyst and silane adhesion promoter and any other additives are added and mixed for an additional 30 minutes to one hour.

Abstract

A moisture curable adhesive composition and use thereof for solar panel assembly. The adhesive composition includes a silane functional poly-α-olefin polymer; a thermoplastic component having a softening point of at least 120°C and selected from the group consisting of thermoplastic elastomers, thermoplastic polymers and combinations thereof, a silane adhesion promoter having a flash point greater than 100°C at atmospheric pressure and a boiling point greater than 100°C at from 0.5 mmHg to 15 mmHg; and optionally, a thermoplastic tackifying agent having a softening point greater than 80°C.

Description

THERMALLY RESISTANT REACTIVE SILANE FUNCTIONAL POLY-ALPHA- OLEFIN HOT MELT ADHESIVE COMPOSITION, METHODS OF USING THE SAME.
AND SOLAR PANEL ASSEMBLY INCLUDING THE SAME
This application claims priority to U.S. Serial No. 61/310,904 filed March, 5, 2010, and U.S. Serial No. 61/310,916, filed March 5, 2010 and U.S. 61/310,834, filed March 5, 2010, which are incorporated herein.
BACKGROUND OF THE INVENTION
The invention is directed to maintaining adhesion between two substrates under challenging environmental conditions.
Solar panels and solar panel fields have unique requirements in that they must maintain their integrity under conditions of high humidity, because they are often positioned out doors and exposed to rain, freezing rain, and snow, and under conditions of widely varying temperature extremes because they are often positioned in hot deserts, on hot asphalt rooftops, and in climates that experience extremely high temperatures, extremely low temperatures, and strong winds. Thus, any mechanism used to secure and maintain solar panels in a fixed position must function under a difficult set of environmental conditions.
SUMMARY OF THE INVENTION
In one aspect, the invention features a moisture curable adhesive composition that includes a silane functional poly-a-olefin polymer; a thermoplastic component having a softening point of at least 120°C and selected from the group consisting of thennoplastic elastomers, thermoplastic polymers, and combinations thereof; a silane adhesion promoter having a flash point greater than 100°C at atmospheric pressure and a boiling point greater than 100°C at from 0.5 mmHg (millimeters of mercury) to 15 mmHg; and optionally, a thermoplastic tackifying agent having a softening point greater than 80°C, and optionally a thennoplastic component having a softening point of lower than 120°C and selected from the group consisting of thermoplastic elastomers, thermoplastic polymers, and combinations thereof.
In one embodiment, the adhesive composition includes a silane functional poly-a- olefin polymer having a softening point of at least 120°C; a silane adhesion promoter having a flash point greater than 100°C at atmospheric pressure and a boiling point greater than 100°C at from 0.5 mmHg (millimeters of mercury) to 15 mmHg; optionally, a thermoplastic tackifying agent having a softening point greater than 80°C; and optionally, a thermoplastic component having a softening point of lower than 120°C and selected from the group consisting of thermoplastic elastomers, thermoplastic polymers, and combinations thereof.
In one embodiment, the adhesive composition includes from about 5 % by weight to about 80 % by weight of the silane functional amorphous poly-a-olefin polymer; and from about 5 % by weight to about 35 % by weight of the thermoplastic tackifying agent.
In one embodiment, the adhesive composition exhibits an initial lap shear of at least 1 psi at 23 °C.
In one embodiment, the adhesive composition further includes a spacer in a form of spheres, cylinders, tubes, strips, ropes, or any other suitable forms.
In another aspect, the invention features a solar panel assembly that includes a solar panel, a support, and a moisture curable adhesive composition disclosed herein, the support being bonded to the solar panel through the adhesive composition. In some embodiments, the solar panel includes a substrate that includes glass, and a superstate, the adhesive
composition being in contact with the glass of the substrate. In one embodiment, the solar panel includes a substrate that includes polymer, and the adhesive composition is in contact with the polymer of the substrate. In another embodiment, the support is metal.
In other embodiments, the support remains bonded to the substrate of the solar panel through the adhesive composition after undergoing the at least one of the Simulated Aging Tests set forth in UL 1703 and the tests set forth in IEC 6646.
In other aspects, the invention features a method of adhering a component of a solar panel assembly to a solar panel, the method including contacting at least one of a first component and a second component with an adhesive composition disclosed herein, the first component including a component of the solar panel assembly other than the solar panel, and the second component including the solar panel, and allowing the adhesive composition to cure to bond the first component to the second component, in one embodiment, the first component includes at least one of a back rail, a frame and a junction box, and the second component includes a substrate of the solar panel, the substrate including at least one of polymer and glass. In other embodiments, the first component includes a metal back rail and the second component includes a substrate of the solar panel, the substrate including at least one of polymer and glass.
The adhesive composition exhibits good green strength, an ability to be handled shortly after application (e.g., an assembly that includes the adhesive composition can be handled shortly after application of the adhesive composition thereto), and, when cured, good durability in a wide range of environmental conditions. The adhesive composition can also be applied using an automated process.
Other features and advantages will be apparent from the following description of the preferred embodiments, the drawings, and from the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plane view a back rail of a solar panel assembly bonded to a substrate of a solar panel through an adhesive composition disclosed herein.
FIG. 2 is a plane view of a junction box of a solar panel assembly bonded to a substrate of a solar panel through an adhesive composition disclosed herein.
FIG. 3 is a plane view of an end bracket of a solar panel assembly bonded to a solar panel through an adhesive composition disclosed herein.
FIG. 4 is a perspective view of a framed solar panel assembly.
FIG. 5 is view taken in cross section along line A-A of the framed solar panel assembly of FIG. 4.
FIG. 6 is a perspective view of a solar panel.
FIG. 7 is an enlarged view of a portion of a framed solar panel assembly with an adhesive/sealant composition configured according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION
In one embodiment, the moisture curable hot melt adhesive composition includes a silane functional poly-a-olefin polymer, a thermoplastic component having a softening point of at least 120°C, and a silane adhesion promoter having a flash point greater than 100°C at atmospheric pressure and a boiling point greater than 100°C at from 0.5 mmHg to 15 mmHg. The adhesive composition cures upon exposure to atmospheric moisture to a composition that exhibits a tensile strength of at least 20 psi at 23 °C, or even at least 70 psi at 23 °C, and at least 20 psi at 85°C, or even at least 70 psi at 85°C.
The adhesive composition preferably exhibits an initial lap shear strength (i.e., green strength) of at least 1 psi, at least 2 psi, or even at least 4 psi at 23°C, and a final lap shear of at least 1 psi, at least 2 psi, or even at least 4 psi at 85°C. Preferably the adhesive composition also exhibits cold temperature flexibility.
The adhesive composition is creep resistant and preferably passes the creep resistance test method at 85°C, or even at a higher temperature than 85°C.
Solar panel assemblies that include the cured adhesive composition preferably pass the Simulated Aging Tests set forth in UL 1703, or even the tests of IEC 6646. The cured adhesive composition preferably maintains a support bonded to a solar panel after undergoing the Simulated Aging Tests set forth in UL 1703, or even the tests of IEC 6646.
SILANE FUNCTIONAL. POLY-A-OLEFIN POLYMERS
Particularly useful silane functional poly-a-olefin polymers are either completely amorphous or have a low level of crystal linity. The degree of crystallinity preferably is no greater than 25 % as determined by X-ray diffraction. Useful silane functional amorphous poly-a-olefin polymers are derived by grafting amorphous poly-a-olefin and a silane source. Suitable amorphous poly-a-olefins include, e.g., homopolymers, copolymers and terpolymers including, e.g., atactic polypropylene, atactic poly-l-butene and combinations thereof. The amorphous poly-a-olefins can be random or block copolymers. Other suitable amorphous poly-a-olefin polymers include, e.g., homogeneous substantially linear ethylene-a-olefin interpolymers of monomers including, e.g., propylene, 1 -butene, 1-pentene, 3-metyI-l -butene, 1-hexene, 3-methyl-l -pentene, 4-methyl-l-pentene, 3 -ethyl- 1 -pentene, 1 -octene, 1-decene, and 1 -undecene; amorphous copolymers with other olefins (e.g., ethylene, 1 -butene, 1- pentene, 1 -hexene, 4-methyl- 1 -pentene, 1 -octene, and 1-decene) containing propylene as a main component, amorphous copolymers with other olefins (e.g., ethylene, propylene, 1- pentene, 1 -hexene, 4-methyl-l -pentene, 1 -octene, 1-decene and the like) containing 1 -butene as a main component; and combinations thereof. Preferred olefm-based amorphous polymers include atactic polypropylene, propylene/ethylene amorphous copolymers, and propylene/1 - butene amorphous copolymers.
One example of a useful class of amorphous poly-a-olefins include copolymers and terpolymers derived from 0 % by weight to 95 % by weight a-olefms having from 4 to 10 carbon atoms, (in other embodiments from 3 % by weight to 95 % by weight), from 5 % by weight to 100 % by weight propane (in other embodiments from 5 % by weight to 97 % by weight), and from 0 % by weight to 20 % by weight ethane as described, e.g., in U.S. Patent No. 5,994,474 and incorporated herein.
The silane to be grafted on the amorphous poly-a-olefin can have two or three alkoxy groups attached directly to the silicon and at least one olefmic double bond containing moiety. Suitable examples include vinyltrimethoxysilane, vinyltriethoxysilane, vinyl tris(2- methoxyethoxy)silane, 3-methacryloxypropyltrimethoxysilane, 3- methacryloxypropyltriethoxysilane, vinyldimethylmethoxysilane and
vinylmethyldibutoxysilane.
The amount silane for grafting on the amorphous poly-a-olefin is from about 0.1 % by weight to about 10 % by weight, from about 2 % by weight to about 6 % by weight, or even from about 3 % by weight to about 5 % by weight, based on the amorphous poly-a-olefin.
Any known method for grafting silane onto the amorphous poly-a-olefin can be used including, e.g., solution and melt (e.g., using an appropriate amount of a free-radical donor) methods. Useful methods of preparing silylated amorphous poly-a-olefin are described, e.g., in U.S. 5,994,474 and DE 40 00 695 and incorporated herein. Suitable examples of free- radical donors include diacyl peroxides such as dilauryl peroxide and didecanoyl peroxide, alkyl peresters such as tert-butyl peroxy-2-ethylhexanoate, perketals such as l ,l -di(tert- butylperoxy)-3,3, 5-trimethylcyclohexane or l,l-di(tert-butylperoxy)cycIohexane, dialkyl peroxides such as tert-butyl cumyl peroxide, di(tert-butyl) peroxide and dicumyl peroxide, C- radical donors including, e.g., 3,4-dimethyl-3,4-diphenylhexane and 2, 3 -dim ethyl -2, 3- diphenylbutane, and azo compounds (e.g., 2,2'-azodi(2-acetoxypropane)).
Preferably the amorphous poly-a-olefin has a number average molecular weight (Mn) from about 7,000 to about 14,000, a weight average molecular weight (Mw) from about 35,000 to about 90,000 and a Z average molecular weight (Mz) from about 13,000 to about 33,000, and polydispersity (MWD) from about 4.9 to about 6.2.
Preferred silane functional amorphous poly-a-olefin polymers include the silane functional amorphous poly-a-olefin polymers that are commercially available under the VESTOPLAST trade designation from Evonik, Germany including, e.g., VESTOPLAST 206V silane functional amorphous poly-a-olefins.
In some embodiments, the silane functional poly-a-olefm polymer has a softening point of less than 120°C. in one embodiment, the silane functional poly-a-olefm polymer has a softening point of at least 120°C.The silane functional poly-a-olefm polymer is present in the composition in an amount of from about 5 % by weight to about 80 % by weight, from about 15 % by weight to about 50 % by weight, or even from about 25 % by weight to about 40 % by weight, based on the weight of the composition. THERMOPLASTIC COMPONENT
The thermoplastic component has a softening point of at least 120°C and includes a thermoplastic elastomer that has a softening point of at least 120°C, a thermoplastic polymer that has a softening point of at least 120°C, or a combination thereof.
In some embodiments, the thermoplastic component having a softening point of at least 120°C is present in the adhesive composition in an amount of from about 10 % by weight to about 75 % by weight, from about 20 % by weight to about 70 % by weight, or even from about 40 % by weight to about 60 % by weight, based on the weight of the composition. In the embodiments where a silane functional poly-a-olefm polymer having a softening point of at least 120°C is used, the thermoplastic component having a softening point of at least 120°C may or may not be present in the adhesive composition.
Suitable thermoplastic elastomers having a softening point of at least 120°C include, e.g., polyetheramide block copolymers, polyesters, butadiene-styrene elastomers including, e.g., A-B, A-B-A, A-(B-A)n-B, (A-B)n-Y, and radial block copolymers and grafted versions thereof where the A block(s) is a polyvinyl aromatic block (e.g., styrene), and the B block is a rubbery midblock (e.g., isoprene, butadiene, efhylene-butylene, and ethylene-propylene) (e.g., styrene-butadiene-styrene block copolymers, styrene-isoprene-styrene block copolymers, styrene-ethylene-butylene-styrene block copolymers, styrene-ethylene-propylene-styrene block copolymers), polyurethane elastomers, polyolefin elastomers, elastomeric ethylene vinyl acetate, ethylene-octene block copolymers, and mixtures thereof.
Useful commercially available thermoplastic elastomers having a softening point of at least 120°C include, e.g., thermoplastic elastomers available under the HYTREL 3078, HYTREL 4053 and HYTREL 4056 trade designations from E.I. DuPont de Nemours
(Worthington, Delaware), styrene-ethylene/butylene-styrene block copolymers available under the KR ATON G series of trade designations including, e.g., KRATON G-1652 and G- 1657, from Kraton Polymers (Houston, Texas); styrene-butadiene-styrene and styrene- isoprene-styrene block copolymers available under the KRATON D series of trade
designations including, e.g., KRATON D-l 1 1 1 and D-l 112 from Kraton Polymers; silane terminated block copolymers available under the KRATON SKFGIOI trade designation from Kraton Polymers; and styrene-butadiene-styrene and styrene-isoprene-styrene block copolymers available under the VECTOR series of trade designations including, e.g.,
VECTOR 41 12, 41 14 and 441 1 from Dexco Polymers (Houston, Texas); ethylene-octene block copolymers available under the INSITE trade designation including e.g., 1NSITE D9807.15 from Dow Chemical Company.
The thermoplastic elastomer having a softening point of at least 120°C can be present in the adhesive composition in an amount of 0 % by weight, or from about 10 % by weight, or from about 20% by weight to about 75% by weight, or to about 60 % by weight, or to about 40 % by weight, based on the weight of the composition.
The thermoplastic polymers having a softening point of at least 120°C can be selected from a variety of classes of thermoplastic polymers including, e.g., polyalkylenes (e.g., polyethylene, polypropylene and polybutylene), poly(alpha)olefins including, e.g., homo-, co- and terpolymers of aliphatic mono- 1 -olefins (alpha olefins) (e.g., poly(alpha)olefms containing from 2 to 10 carbon atoms), homogeneous linear or substantially linear
interpolymers of ethylene having at least one C3 to C20 alpha olefin, polyisobutylenes, poly(alkylene oxides), polyfphenylenediamine terephthalamide), polyesters (e.g.,
polyethylene terephthalate), polyacrylates, polymethacrylates, polyacrylamides,
polyacrylonitriles, copolymers of acrylonitrile and monomers including, e.g., butadiene, styrene, polymethyl pentene, and polyphenylene sulfide (e.g., styrene-acrylonitrile, acrylonitrile-butadiene-styrene, acrylonitrile-styrene-butadiene rubbers), polyimides, polyamides, copolymers of vinyl alcohol and ethylenically unsaturated monomers, polyvinyl acetate (e.g., ethylene vinyl acetate), polyvinyl alcohol, vinyl chloride homopolymers and copolymers (e.g., polyvinyl chloride), terpolymers of ethylene, carbon monoxide and acrylic acid ester or vinyl monomer, polysiloxanes, polyuremanes, polystyrene, and combinations thereof, and homopolymers, copolymers and terpolymers thereof, and mixtures thereof. Other useful classes of thermoplastic polymers include asphalts, bitumens, crude rubbers, fiuorinated rubbers, and cellulosic resins.
Useful commercially available thermoplastic polymers having a softening point of at least 120°C include, e.g., amorphous polyalphaolefins available from Evonik under the trade designations VESTOPLAST 308, VESTOPLAST 608, and VESTOPLAST 703, atactic polypropylene polymers available under the REXTAC series of trade designations including, e.g., REXTAC RT 2535 and RT 2585, from REXtac LLC (Odessa, Texas) and the
EASTOFLEX series of trade designations including, e.g., EASTOFLEX El 060, from
Eastman Chemical Co. (Kingsport, Tennessee); polyethylene polymers available under the EPOLENE C-17 trade designation from Westlake Chemical Corporation; ethylene methyl acrylate copolymers available under the OPTEMA series of trade designations from ExxonMobil Chemical Co. (Houston, Texas); and butylene/poly(alkylene ether) phthalate polymers available under the HYTREL trade designations from DuPont.
The thermoplastic polymer having a softening point of at least 120°C is preferably present in the adhesive composition in an amount of 0 % by weight, or from about 10 % by weight, or from about 20% by weight to about 75% by weight, or to about 60 % by weight, or to about 40 % by weight, based on the weight of the composition.
SILANE ADHESION PROMOTER
The adhesive composition also includes a silane adhesion promoter that has a flash point greater than 100°C at atmospheric pressure and a boiling point greater than 100°C at from 0.5 mmHg to 15 mmHg. Silane adhesion promoters are compounds or monomers that have an average molecular weight of from about 300 to about 1000, or from about 300 to about 800, or from about 500 to about 700. Useful silane adhesion promoters include silyl groups such as alkoxysilyls, acryloxysilyls, alkyloxyiminosilyls, oxime silyls, amino silyls, and combinations thereof. Examples of useful alkoxysilyl groups include methoxysilyl, ethoxysilyl, propoxysilyl, butoxysilyl, and acyloxysilyl reactive groups including, e.g., silyl ester of various acids including, e.g., acetic acid, 2-ethylhexanoic acid, palmitic acid, stearic acid, and oleic acid.
Suitable silane adhesion promoters include, e.g., methacryloxy propyl triethoxy-silane, M-aminophenyltriethoxy-silane, P-aminophenyltriethoxy-silane, N-(2-aminoethyl)-3- aminopropyl triethoxy-silane, n-butylaminopropyltrimethoxy-silane,
bis(triethoylsilylpropyl)amine, bis(trimethoylsilylpropyl) amine, 3-(trimethoxylsilyl) propyl succinic anhydride, (3-glycidoxypropyl) methyldiethoxy-silane, (3-glycidoxypropyl) methyldimethoxy-silane, tris(3-trimethoxysilylpropyl) isocyanurate, bis(triethoxysilyl)ethane, bis(trimethoxysilyl) benzene, and combinations thereof.
Suitable silane adhesion promoters are commercially available under the SILQUEST A-l 170 and SILQUEST SILQUEST A-LINK 597 trade designations from Momentive Performance Materials, Inc. (Albany, New York). The silane adhesion promoter is preferably present in the composition in an amount of from about 0.01 % by weight to about 5 % by weight, from about 0.01 % by weight to about 2 % by weight, or even from about 0.01 % by weight to about 1 % by weight, based on the weight of the composition.
OTHER INGREDIENTS/ADDITIVES
The adhesive composition may also include other optional ingredients e.g., a thermoplastic component having a soften point of less than 120°C, a thermoplastic tackifying agent having a ring and ball softening point of at least 80°C, and combinations thereof.
Useful thermoplastic components having a soften point of less than 120°C include such as thermoplastic elastomers having a soften point of less than 120°C, thermoplastic polymers having a soften point of less than 120°C, and combinations thereof. Examples of useful thermoplastic components include all the classes of the thermoplastic components listed above.
Examples of useful thermoplastic elastomers having a soften point of less than 120°C include e.g., polyisobutylene, butyl rubber, ethylene/propylene/diene rubber (i.e., EPDM rubber), and combinations thereof. Commercially available examples of useful thermoplastic elastomers having a soften point of less than 120°C include e.g., polyisobutylenes available under the OPPANOL series of trade designations including B50, B80, B100, B 150, B200, B246, B12 and B15 trade designation from BASF (Germany); polyisobutylenes available under the VISTANEX series of trade designations from ExxonMobil including VISTANEX LMMS, MML-80, MML-100, MML-120, and MML 140; isobutylene-isoprene copolymers available the BUTYL Rubber series of trade designations including BUTYL 268 and BUTYL 065 from ExxonMobil Chemical Co. (Houston, Texas); ethylene-propylene copolymers available under the VISTALON series of trade designations including, e.g., V1STALON 404, from ExxonMobil Chemical Co.
Commercially available examples of useful thermoplastic polymers having a soften point of less than 120°C include e.g., ethylene vinyl acetate copolymers available under the ATEVA series of trade designations from AT Plastics ( Brampton, Ontario, Canada) including ATEVA 4030MC and ATEVA 1850, the ELVAX series of trade designations from DuPont de Nemours (Wilmington, Delaware) and the ULTRATHENE series of trade designations from Millennium Petrochemicals (Rolling Meadows, Illinois); ethylene n-butyl acrylate copolymers available under the LOTRYL series of trade designations from Elf Atochem North America (Philadelphia, Pennsylvania), the ESCORENE series of trade designations from ExxonMobil Chemical Co. and the EN ATHENE series of trade
designations from Millennium Petrochemicals; ethylene n-butyl acrylate carbon monoxide terpolymers available under the ELVALOY series of trade designations from DuPont;
thermoplastic polyurethane polymers available under the PEARLSTICK series of trade designations from Aries Technologies (Derry, New Hampshire a distributor for Merquinsa,
Barcelona, Spain); ethylene acrylate copolymers also available under the ELVALOY series of trade designations from DuPont; and acrylic polymers available under the ELVACITE series of trade designations from ICI Acrylics (St. Louis, Missouri); useful commercially available homogeneous linear or substantially linear interpolymers of ethylene having at least one C3 to C?o alpha olefin and a polydispersity less than about 2.5 include, e.g., EXACT 5008 ethylene- butene copolymer, EXXPOL SLP-0394 ethylene-propylene copolymer, and EXACT 3031 an ethylene-hexene copolymer from ExxonMobil Chemical Co. (Houston, Texas) and ethylene/1. -octene polymers available under the trade designation AFFINITY from Dow Chemical Co. (Midland, Michigan).
The thermoplastic component having a softening point of less than 120°C is preferably present in the adhesive composition in an amount of from 0 % by weight, to about 20 % by weight, based on the total weight of the composition.
Preferred thermoplastic tackifying agents have a ring and ball softening point of at least 80°C, or even from about 85°C to about 150°C. The tackifying agent preferably is free of groups with which the silanol group of the silyated amorphous poly-a-olefm will react. Examples of suitable tackifying agents include aliphatic, cycloaliphatic, aromatic, aliphatic- aromatic, aromatic modified alicyclic, and alicyclic hydrocarbon resins and modified versions and hydrogenated derivatives thereof; terpenes (polyterpenes), styrenated teipenes, modified terpenes (e.g., phenolic modified terpene resins), hydrogenated derivatives thereof, and combinations thereof; alpha methyl styrene resins and hydrogenated derivatives thereof; and combinations thereof. Other useful tackifying agents are disclosed in. e.g., U.S. Patent No. 6,355,317, and incorporated herein.
Other tackifying agents include natural and modified rosins such as gum rosin, wood rosin, tall oil rosin, distilled rosin, completely or partially hydrogenated rosin, dimerized rosin and polymerized rosin; rosin esters including, e.g., glycerol and pentaerythritol esters of natural and modified rosins, (e.g., glycerol esters of pale, wood rosin, glycerol esters of hydrogenated rosin, glycerol esters of polymerized rosin, pentaerythritol esters of
hydrogenated rosin and phenolic-modified pentaerythritol esters of rosin); alpha methyl styrene resins and hydrogenated derivatives thereof; low molecular weight polylactic acid; and combinations thereof.
Suitable commercially available tackifying agents include, e.g., cycloaliphatic hydrocarbon resins and aromatic-modified, cycloaliphatic hydrocarbon resins available under the ESCOREZ 5637 and ESCOREZ 5340 trade designations from Exxon Mobile Chemical Company; partially hydrogenated cycloaliphatic petroleum hydrocarbon resins available under the EASTOTAC series of trade designations (e.g., EASTOTAC H-130 and H-142) from Eastman Chemical Co. (Kingsport, Tennessee) available in grades E, R, L and W, which have differing levels of hydrogenation from least hydrogenated (E) to most hydrogenated (W), the ESCOREZ series of trade designations including, e.g., ESCOREZ 5320 and
ESCOREZ 5400, from ExxonMobil Chemical Co. (Houston, Texas), and under the
HERCOLITE 2100 trade designation from Eastman Chemical Co.; partially hydrogenated aromatic modified petroleum hydrocarbon resins available under the ESCOREZ 5600 trade designation from ExxonMobil Chemical Co.; aromatic hydrogenated hydrocarbon resins available under the trade designation REGALREZ 1 126 and alphamethyl styrene resins available under the trade designation KRISTALEX 5140 from Eastman Chemical Co.
(Kingsport, Tennessee).
The tackifying agent is preferably present in the composition in an amount of from about 0 % by weight, or from about 5 % by weight to about 15 % by weight, or to about 20 % by weight, or to about 35 % by weight, based on the weight of the composition. The adhesive composition may also include other additives including, e.g., fillers, waxes, plasticizers, thermal stabilizers, light stabilizers (e.g., UV light stabilizers and absorbers), optical brighten ers, antistats, lubricants, antioxidants, catalysts, rheology modifiers, biocides, corrosion inhibitors, dehydrators, organic solvents, colorants (e.g., pigments and dyes), surfactants antiblocking agents, nucleating agents, flame retardants and combinations thereof. The type and amount of other additives is selected to minimize the present of moisture that can prematurely initiate cure of the sealant.
Suitable fillers include, e.g., fumed silica, precipitated silica, talc, calcium carbonates, carbon black, alumina silicates, clay, zeolites, ceramics, mica, titanium dioxide, and combinations thereof. The composition can include filler in an amount of from 0 % by weight to about 40 % by weight, from about 10 % by weight to about 35 % by weight, or even from about 20 % by weight to about 30 % by weight, based on the weight of the composition.
The plasticizer preferably has a boiling point of greater than about 85°C. Preferred plasticizers include paraffinic oils, naphthenic oils, low molecular weight poly- 1 -but ene, low molecular weight polyisobutene, and combinations thereof Plasticizer can be present in the composition in an amount of from 0 % by weight to about 10 % by weight, based on the weight of the composition.
A crosslinking accelerator can be added to the composition to increase the rate of crosslinking. Useful crosslinking accelerators include, e.g., organotin compounds including, e.g., dialkyl tin dicarboxylates (e.g., dibutyl tin dilaurate and dibutyl tin diacetate), tin carboxylates, tertiary amines, stannous salts of carboxylic acids, e.g., stannous octoate and stannous acetate, tetrabutyl dioleatodistannoxane, titanium compounds, organosilicon titantates, alkyltitantates, and metal alkoxides (e.g., aluminum isopropoxide and zirconium isopropoxide), and combinations thereof. The accelerator can be added either in pure form or, for greater ease of metering, in the form of a master batch that includes the amorphous poly- a-olefm. The accelerator can be added to the composition before melting, in the form of a dry mix, or after melting. Accelerator preferably is present in amounts from 0.001 % by weight to 5 % by weight, or even from 0.01 % by weight to 1 % by weight, based on the weight of the composition. USE
The adhesive composition is useful for bonding a variety of substrates to each other including substrates made from, e.g., glass, polymer (e.g., polymer composites), metal (e.g., stainless steel, aluminum (e.g., anodized aluminum), galvanized steel and cold-rolled steel), and combinations thereof, treated and coated substrates (e.g., substrates treated for corrosion resistance, aluminum and zinc coated substrates, and combinations thereof), painted substrates and combinations thereof.
The adhesive composition is useful for bonding the various components of a solar panel assembly to each other including such components as, e.g., solar panel frames (e.g., C- shaped channels), junction boxes (e.g., polymeric junction boxes), back rails for supporting solar panels (e.g., metal back rails), , brackets (e.g., end brackets), solar panels, components of solar panels (e.g., superstrate, substrate and edges), components used in mounting the solar panels, components used in supporting the solar panels, and combinations thereof. Useful solar panel superstrates include a layer of an ultra violet light transparent material (e.g., glass), and useful solar panel substrates include a layer of polymer, polymer composite, and combinations thereof.
In one embodiment, the aforesaid adhesive composition is particularly used for sealing and mounting frames on a solar panel to form a framed solar panel assembly.
Solar panels are often surrounded by a frame and adhered to the frame with a structural adhesive. It is often necessary to include both a structural adhesive and a moisture vapor barrier to achieve a framed solar panel that will maintain its integrity under the rigorous conditions to which it is often exposed including, e.g., high humidity, widely varying temperature extremes, and strong winds.
In the embodiments where it is used for framing solar panels, the aforesaid adhesive composition can function as both an adhesive and a moisture vapor barrier, therefore, is referred to as an adhesive/sealant composition. In some embodiments, the adhesive/sealant composition exhibits a moisture vapor transmission rate (MVTR) of no greater than 2 g/m2/day. In some embodiments, the adhesive/sealant composition exhibits a MVTR of no greater than 1 g/m /day. In some embodiments, the adhesive/sealant composition exhibits a MVTR of no greater than 0.2 g/m2/day.
In one embodiment, the invention provides a framed solar panel assembly. The solar panel assembly includes a solar panel that includes edges; a peripheral frame including an interior surface; and any one of the aforesaid adhesive/sealant compositions disposed between the interior surface of the frame and the edges of the solar panel, the panel being bonded to the frame through the adhesive/sealant composition.
In another embodiment, the invention provides a method of framing a solar panel. The method includes contacting at least one of the interior surfaces of a frame and the solar panel with any one of the adhesive/sealant compositions disclosed herein, and affixing the frame to the solar panel. In some embodiments the method further includes allowing the adhesive/sealant composition to cure such that the frame is bonded to the solar panel through the cured adhesive/sealant composition.
The framed solar panel assemblies exhibit good protection against moisture, which can adversely affect the efficiency of the solar panel. The method provides an efficient framing process and enables the manufacture of a framed solar panel assembly using an adhesive/sealant composition that functions as both an adhesive composition and a sealant composition at the same time, especially as an edge sealant composition.
Other features and advantages of the invention will be apparent from the following description of the preferred embodiments, the drawings, and from the claims.
Turning to FIG. 1 , a back rail 10 of a solar panel assembly 5 is bonded to a substrate 8 of a solar panel 12 through an adhesive composition 6.
FIG. 2 illustrates a junction box 20 bonded to a substrate 8 of a solar panel 12 through an adhesive composition 6.
Referring to FIG. 3, an end bracket 30 is bonded to an edge 22, substrate 8 and superstrate 24 of a solar panel 12 through an adhesive composition 6.
FIGS. 4-6 illustrate a framed solar panel assembly 1 1 includes a solar panel 12 and a peripheral frame 14. The solar panel 12 is surrounded by the frame 14 along edges 16, 18, 20, and 22. An adhesive/sealant composition 4 is disposed between the edges 16, 18, 20 and 22 and the interior surface 28 of the frame 14 so as to seal the solar panel 12, which provides a barrier to moisture entering the solar panel 12, and to adhere the frame 14 to the edges 16, 18, 20 and 22 of the solar panel 12. A continuous bead of the adhesive/sealant composition 4 is in continuous contact with the edge of the solar panel 12 to form a vapor barrier.
The frame 14 defines a U-shaped channel 32 that receives an edge of the solar panel 12. The channel 32 includes a back wall 34, a top wall 36, and a bottom wall 38. The adhesive/sealant composition 4 is in contact with at least one component of the channel 32 of the frame 14, e.g., the back wall 34, a top wall 36, and a bottom wall 38 of the frame 14, and at least one component of the solar panel 12, e.g., the edges 16, 18, 20, and 22 of the panel 12, the superstrate 24 (e.g., a glass superstrate) of the solar panel 12, and the substrate 8 (e.g., a polymer substrate or a glass substrate) of the solar panel 12, as shown in FIG. 6.
Turning to FIG. 7, the adhesive/sealant composition 4 is positioned in a discontinuous manner on the bottom wall 38, back wall 34, and top wall 36 of the channel 32 of the frame 14 that receives the solar panel 12. The adhesive/sealant composition 4 bonds the frame 14 to the solar panel 12 and preferably provides a vapor barrier. The adhesive/sealant composition 4 preferably exhibits a moisture vapor transmission rate (MVTR) of no gi'eater than 2 g/m2/day, when in the form of a 60 mil film.
Other solar panel assemblies in which the adhesive composition is particularly useful include those constructions described in, e.g., U.S. 2009/0205703 and U.S. 2010/0018570, which are incorporated herein.
The invention will now be described by way of the following examples. All parts, ratios, percents and amounts stated in the Examples are by weight unless otherwise specified
EXAMPLES
Test Procedures
Test procedures used in the examples include the following.
Tensile Strength Test Method
The tensile strength at break is determined according to ASTM-D638-00 entitled, "Standard Test Method for Tensile Properties of Plastics." A homogeneous film of the adhesive composition is pressed to a thickness of from 40 mil to 60 mil. The film is conditioned at 23 °C and 50 % relative humidity for 12 weeks to cure. Specimens are cut from the film and tested for tensile strength at break according to ASTM D638-00. Lap Shear Strength Test Method
The lap shear strength is determined according to ASTM C-961-01 entitled. "Standard Test Method for Lap Shear Strength of Hot Applied Sealants," with the exception that the test specimen is prepared as follows. A 1 in x 1 in film of adhesive composition having a thickness of from 50 mil to 60 mil is placed on a 4 in x 1 in piece of a first substrate (stainless steel). A 1 in x 3 in piece of a second substrate {stainless steel) is then placed on top of the film and pressed hard against the film using maximum hand pressure. The test specimen is then heated to a temperature of from 120°C-150°C for 10 minutes to achieve good wet out of the adhesive composition.
Initial lap shear (i.e., green strength) is measured within about one to two hours after preparing the bond sample.
Final lap shear is measured 12 weeks after preparing the bond sample.
Creep Resistance Test Method
Creep resistance is determined as follows. A 1 in x 1 in film of adhesive composition having a thickness of from 50 mil to 60 mil is placed on a 4 in x 1 in piece of aluminum. A 1 in x 3 in piece of glass is then placed on top of the film and pressed hard against the film using maximum hand pressure. The test specimen is then heated to a temperature of from 120°C to 150°C for 10 minutes to achieve good wet out of the adhesive composition. The test specimen is allowed to cure for at least 4 weeks.
A one pound load is then hung from an end of the test specimen and placed in an oven at a specified temperature, e.g., at 85 °C or even a higher temperature. The time to failure is recorded. The test specimen is recorded as pass at the test temperature if there is no failure after seven days. Cold Temperature Flexibility Test Method
Flexibility is measured according to ASTM D31 1 1 entitled, ''Flexibility Determination of Hot Melt Adhesive by Mandrel Bend Test Method" (which is incorporated herein) using a free film. The results are reported as pass or fail according to the criteria set forth in ASTM D31 1 1.
Examples 1 and 2
Moisture curable hot melt adhesive compositions of Examples 1 and 2 are prepared according to Table I by mixing all thermoplastic polymer(s), polyols, and tackifier (if added) in a molten state until uniformly blended. The silane tenninated APAO is then added and mixed under vacuum for 1 -3 hours. Catalyst and silane adhesion promoter and any other additives are added and mixed for an additional 30 minutes to one hour.
The adhesive compositions of Examples 1 and 2 are tested according to the test methods disclosed herein, and the results are also listed in Table 1.
Table I
Figure imgf000019_0001
The relevant portions of all documents disclosed herein are hereby incorporated by reference in their entirety.
Other embodiments are within the claims.
What is claimed is:

Claims

A moisture curable adhesive composition comprising:
a silane functional poly-a-olefin polymer;
a thermoplastic component having a softening point of at least 120°C and selected from the group consisting of thermoplastic elastomers, thermoplastic polymers and combinations thereof;
a silane adhesion promoter having a flash point greater than 100°C at atmospheric pressure and a boiling point greater than 100°C at from 0.5 mmHg to 15 mmHg; and
optionally, a thermoplastic tackifying agent having a softening point greater than 80°C.
The moisture curable adhesive composition of claim 1 , comprising:
from about 5 % by weight to about 80 % by weight of the silane functional amorphous poly-a-olefin polymer; and
from about 5 % by weight to about 35 % by weight of the thermoplastic tackifying agent.
3. The moisture curable adhesive composition of claim 1 , further comprising a thermoplastic component having a softening point of less than 120°C.
A moisture curable adhesive composition comprising:
a silane functional poly-a-olefin polymer having a softening point of at least a silane adhesion promoter having a flash point greater than 100°C at atmospheric pressure and a boiling point greater than 100°C at fi-om 0.5 mmHg to 1 mmHg; optionally, a thermoplastic component having a softening point of less than 120°C, and selected from the group consisting of thermoplastic elastomers, thermoplastic polymers and combinations thereof; and
optionally, a thermoplastic tackifying agent having a softening point greater than 80°C.
5. A solar panel assembly comprising:
a solar panel;
a support; and
the moisture curable adhesive composition of any one of claims 1 -4, the support being bonded to the solar panel through the adhesive composition.
6. The solar panel assembly of claim 5, wherein the solar panel comprises a substrate comprising glass and a superstrate, the adhesive composition being in contact with the glass of the substrate.
7. The solar panel assembly of claim 5, wherein the solar panel comprises a substrate comprising polymer, the adhesive composition being in contact with the polymer of the substrate.
8. The solar panel assembly of claim 5, wherein the adhesive composition further comprises a spacer.
9. A method of adhering a component of a solar panel assembly to a solar panel, the method comprising:
contacting at least one of a first component and a second component with the adhesive composition of any one of claims 1-4. the first component comprising a component of the solar panel assembly other than the solar panel, and the second component comprising the solar panel, and allowing the adhesive composition to cure to bond the first component to the second component.
10. The method of claim 9, wherein the first component comprises at least one of a back rail, a frame, and a junction box, and the second component comprises a substrate of the solar panel, the substrate comprising at least one of polymer and glass.
1 1. The method of claim 9, wherein the first component comprises a metal back rail and the second component comprises a substrate of the solar panel, the substrate comprising at least one of polymer and glass.
12. The method of claim 1 1 , wherein the adhesive composition further comprises spacer.
13. A framed solar panel assembly, comprising:
a solar panel comprising edges;
a peripheral frame comprising an interior surface; and
a moisture curable adhesive/sealant composition disposed between the interior surface of the frame and the edges of the panel, the panel being bonded to the frame through the adhesive/sealant composition, the adhesive/sealant composition comprising
a silane functional poly-a-olefm polymer;
a thermoplastic component having a softening point of at least 120°C and selected from the group consisting of thermoplastic elastomers, thermoplastic polymers and combinations thereof;
a silane adhesion promoter having a flash point greater than 100°C at atmospheric pressure and a boiling point greater than 100°C at from 0.5 mmHg to 15 mmHg; and
optionally, a thermoplastic tackifying agent having a softening point greater than 80°C.
14. The framed solar panel assembly of claim 13, wherein the adhesive/sealant composition exhibits an MVTR of no greater than 2 g/m7day.
15. A method of framing a solar panel, the method comprising:
contacting at least one of the interior surfaces of a frame with a solar panel by means of a moisture curable adhesive/sealant composition, and
affixing the frame to the solar panel,
the adhesive/sealant composition comprising
a silane functional poly-a-olefin polymer;
a thermoplastic component having a softening point of at least 120°C;
a silane adhesion promoter having a flash point greater than 100°C at atmospheric pressure and a boiling point greater than 100°C at from 0.5 mmHg to 15 mmHg; and
optionally, a thermoplastic tackifying agent having a softening point greater than 80°C.
16. The method of claim 15, further comprising allowing the adhesive/sealant composition to cure such that the frame is bonded to the solar panel through the cured adhesive/sealant composition.
17. The method of claim 15, wherein the adhesive/sealant composition exhibits an MVTR of no greater than 2 g/m2/day.
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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2607442A1 (en) * 2011-12-19 2013-06-26 Sika Technology AG Reactive polyolefin hotmelt with low viscosity and its use for textile lamination
WO2014041033A1 (en) 2012-09-11 2014-03-20 Sika Technology Ag Reactive polyolefin hot-melt adhesive for use as a pre-coating that can be reactivated
KR20150004813A (en) * 2012-04-27 2015-01-13 헨켈 아게 운트 코. 카게아아 Hot-melt adhesive for electric instruments
EP3369782A4 (en) * 2015-12-07 2019-06-12 Moresco Corporation Hot melt composition, hot melt composition production method, seal material, electronic device, and lamp
US10787596B2 (en) 2017-03-09 2020-09-29 H. B. Fuller Company Reactive hot melt adhesive having high initial strength, good heat stability and low monomeric diisocyanate
CN113897159A (en) * 2021-11-29 2022-01-07 杭州汉高新材料科技有限公司 Continuous online forming warm edge division bar sealant and manufacturing method thereof
CN116179137A (en) * 2023-03-06 2023-05-30 东莞市德聚胶接技术有限公司 Low-water vapor transmittance moisture-curable polyurethane hot melt adhesive

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4000695A1 (en) 1990-01-12 1991-07-18 Huels Chemische Werke Ag METHOD FOR PRODUCING MOST AMORPHOUS POLYALPHAOLEFINS WITH A NARROW MOLECULAR WEIGHT DISTRIBUTION
US5994474A (en) 1996-09-04 1999-11-30 Heuls Aktiengesellschaft Use of silane-grafted amorphous poly-α-olefins as moisture-crosslinking adhesive base material or adhesive
US6355317B1 (en) 1997-06-19 2002-03-12 H. B. Fuller Licensing & Financing, Inc. Thermoplastic moisture cure polyurethanes
US20030050401A1 (en) * 2000-11-06 2003-03-13 Peter Jackson Crosslinked, predominantly polypropylene-based compositions
WO2004019421A1 (en) * 2002-08-21 2004-03-04 Truseal Technologies, Inc. Solar panel including a low moisture vapor transmission rate adhesive composition
US20040180154A1 (en) * 2003-03-11 2004-09-16 Bing Wang One-part moisture curable hot melt silane functional poly-alpha-olefin sealant composition
US20090205703A1 (en) 2008-02-14 2009-08-20 Applied Materials, Inc. Apparatus and method of mounting and supporting a solar panel
US20100018570A1 (en) 2008-05-16 2010-01-28 Cashion Steven A Concentrating photovoltaic solar panel

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4000695A1 (en) 1990-01-12 1991-07-18 Huels Chemische Werke Ag METHOD FOR PRODUCING MOST AMORPHOUS POLYALPHAOLEFINS WITH A NARROW MOLECULAR WEIGHT DISTRIBUTION
US5994474A (en) 1996-09-04 1999-11-30 Heuls Aktiengesellschaft Use of silane-grafted amorphous poly-α-olefins as moisture-crosslinking adhesive base material or adhesive
US6355317B1 (en) 1997-06-19 2002-03-12 H. B. Fuller Licensing & Financing, Inc. Thermoplastic moisture cure polyurethanes
US20030050401A1 (en) * 2000-11-06 2003-03-13 Peter Jackson Crosslinked, predominantly polypropylene-based compositions
WO2004019421A1 (en) * 2002-08-21 2004-03-04 Truseal Technologies, Inc. Solar panel including a low moisture vapor transmission rate adhesive composition
US20040180154A1 (en) * 2003-03-11 2004-09-16 Bing Wang One-part moisture curable hot melt silane functional poly-alpha-olefin sealant composition
US20090205703A1 (en) 2008-02-14 2009-08-20 Applied Materials, Inc. Apparatus and method of mounting and supporting a solar panel
US20100018570A1 (en) 2008-05-16 2010-01-28 Cashion Steven A Concentrating photovoltaic solar panel

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103958632A (en) * 2011-12-19 2014-07-30 Sika技术股份公司 Reactive polyolefin hot-melt adhesive having low viscosity and use thereof for textile laminations
WO2013092575A1 (en) 2011-12-19 2013-06-27 Sika Technology Ag Reactive polyolefin hot-melt adhesive having low viscosity and use thereof for textile laminations
EP2607442A1 (en) * 2011-12-19 2013-06-26 Sika Technology AG Reactive polyolefin hotmelt with low viscosity and its use for textile lamination
EP2841519B1 (en) * 2012-04-27 2018-08-15 Henkel AG & Co. KGaA Electric instruments comprising a hot-melt adhesive
KR20150004813A (en) * 2012-04-27 2015-01-13 헨켈 아게 운트 코. 카게아아 Hot-melt adhesive for electric instruments
KR102140351B1 (en) * 2012-04-27 2020-07-31 헨켈 아게 운트 코. 카게아아 Hot-melt adhesive for electric instruments
EP2895571B1 (en) 2012-09-11 2017-11-15 Sika Technology AG Reactive polyolefin hot melt adhesive for use as reactivatable pre-coating
WO2014041033A1 (en) 2012-09-11 2014-03-20 Sika Technology Ag Reactive polyolefin hot-melt adhesive for use as a pre-coating that can be reactivated
EP3369782A4 (en) * 2015-12-07 2019-06-12 Moresco Corporation Hot melt composition, hot melt composition production method, seal material, electronic device, and lamp
US10975272B2 (en) 2015-12-07 2021-04-13 Moresco Corporation Hot melt composition, hot melt composition production method, seal material, electronic device, and lamp
US10787596B2 (en) 2017-03-09 2020-09-29 H. B. Fuller Company Reactive hot melt adhesive having high initial strength, good heat stability and low monomeric diisocyanate
CN113897159A (en) * 2021-11-29 2022-01-07 杭州汉高新材料科技有限公司 Continuous online forming warm edge division bar sealant and manufacturing method thereof
CN116179137A (en) * 2023-03-06 2023-05-30 东莞市德聚胶接技术有限公司 Low-water vapor transmittance moisture-curable polyurethane hot melt adhesive
CN116179137B (en) * 2023-03-06 2023-10-13 广东德聚技术股份有限公司 Low-water vapor transmittance moisture-curable polyurethane hot melt adhesive

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