SILICA GEL COMPOSITION AND METHOD FOR MAKING
BACKGROUND OF THE INVENTION
The instant invention relates to silica gel compositions containing acidified cation exchanging layered silicate materials and methods for preparing such compositions.
As is well known in the art (see, for example, Chapter 3 of Applied Industrial Catalysis, Volume 3, Edited by Bruce E. Leach, 1984, Academic Press, ISBN 0-12-440203- 8) silica gel can be prepared by mixing a water-soluble alkaline metal silicate and an acid. The alkaline metal silicate reacts with the acid to form a hydrogel that is then dried to form the silica gel. It is also well known that silica gel can be used as a catalyst support.
It is known that certain ion exchanged layered silicate materials can activate some metaUocene complexes for the polymerization of alpha olefins, see, for example, US Patent 5,308,811 and European Patent 658,576. Furthermore, metaUocene catalysts are generally deposited on a support to function in particle forming polymerization processes, such as gas and slurry phase polymerizations. In addition, the physical properties of the support are important, see, for example, Karol, J. Polym. Mater. Sci. Eng. 80(1999) 277.
In the ion exchanged layered silicate activator literature, the clay activator functions both as the metaUocene activator and the metaUocene support. Unfortunately, such prior art clay activator/supports often do not possess the physical properties needed in certain particle forming polymerization processes. For example, low catalyst activity and/or poor polymer morphology can result. It would be an advance in the art if ion exchanged layered silicate based metaUocene activator/support system could be developed that overcame these problems.
SUMMARY OF THE INVENTION The instant invention is a solution, at least in part, to the above-mentioned problem.
The instant invention combines the excellent attributes of the ion exchanged layered silicate metaUocene activators with the excellent physical characteristics of a silica gel catalyst support.
The instant invention is a composition of matter comprising more than one percent acidified cation exchanging layered silicate material dispersed in more than one percent silica gel.
In another embodiment, the instant invention is a method for producing a 5 silica gel composition, comprising two steps. The first step is to mix a cation exchanging layered silicate material with an acid and an alkaline metal silicate so that the cation exchanging layered silicate material is acidified and so that the alkaline metal silicate precipitates as silica hydrogel. The second step is to dry the silica hydrogel to produce a silica gel composition having the acidified cation exchanging layered silicate material 0 dispersed therewith, the composition having more than one percent acidified cation exchanging layered silicate material and more than one percent silica gel.
In another embodiment, the instant invention method for producing a silica gel composition, comprising three steps. The first step is to mix a mixture of silica gel and water to produce a silica gel slurry. The second step is to mix an acid treated cation 5 exchanging layered silicate material with the silica gel slurry to produce a mixed slurry. The third step is to spray dry the mixed slurry to produce the silica gel composition, the silica gel composition having more than one percent acidified cation exchanging layered silicate material and more than one percent silica gel.
In yet another embodiment, the instant invention is a method for producing a o silica gel composition, comprising three steps. The first step is to mix analkaline metal silicate with an acid to produce a silica hydrogel slurry. The second step is to mix the silica hydrogel slurry with a cation exchanging layered silicate material to produce a slurry of acidified cation exchanging layered silicate material and silica hydrogel. The third step is to dry the slurry of acidified cation exchanging layered silicate material and silica hydrogel to 5 produce the silica gel composition, the silica gel composition having more than one percent acidified cation exchanging layered silicate material and more than one percent silica gel.
In yet another embodiment, the instant invention is a method for producing a silica gel composition, comprising two steps. The first step is to mix silica gel particles, particles of cation exchanging layered silicate material, an acid and water, the silica gel o having pores therein, at least a portion of the pores of the silica gel being large enough to allow the entry of at least a portion of the particles of acidified cation exchanging layered
silicate material into the pores of the silica gel. The second step is to dry the silica gel particles to produce the silica gel composition, the silica gel composition having more than one percent acidified cation exchanging layered silicate material and more than one percent silica gel having more than one percent acidified cation exchanging layered silicate material 5 and more than one percent silica gel.
DETAILED DESCRIPTION OF THE INVENTION
The instant invention is a composition of matter, comprising more than one percent acidified cation exchanging layered silicate material dispersed in more than one percent silica gel. Preferably, the amount of acidified cation exchanging layered silicate 0 material and silica gel is more than fifty percent by weight of the composition of the instant invention. Most preferably, the composition of the instant invention consists essentially of the acidified cation exchanging layered silicate material and the silica gel.
Examples of cation exchanging layered silicate materials include:
I) biophilite, kaolinite, dickalite or talc clays, 5 2) smectite clays,
3) vermiculite clays,
4) mica,
5) brittle mica,
6) Magadiite 0 7) Kenyaite,
8) Octosilicate,
9) Kanemite,
10) Makatite, and
I I) Zeolitic layered materials such as ITQ-2, MCM-22 precursor, exfoliated 5 ferrierite and mordenite.
The above clay materials exist in nature, and also can be synthesized, generally in higher purity than the native material. Any of the naturally occurring or synthetic cation exchanging layered silicate clay materials may be used in the present invention alone or as a mixture. Preferred are smectite clays, including montmorillonite, o bidelite, saponite and hectorite. The term "cation exchanging layered silicate material" used
herein also includes the "layered fiber" silicate materials such as attapulgite and sepiolite. In its broadest coverage, the term "cation exchanging layered silicate material" used herein means any cation exchanging silicate material having at least one dimension in the 1-100 nanometer size range as dispersed in the nanocomposite polymer. The cation exchanging layered silicate material is acidified by contacting it with a Bronsted acid (e.g., hydrochloric acid or sulfuric acid or any material which forms an acidic aqueous dispersion such as acidic metal salts like zinc sulfate) or by contacting it with an acidified amine (e.g., ammonium sulfate or an amine hydrochloride such as 4-tetradecyl aniline hydrochloride). Preferably, essentially all of the available cation exchange sites of the layered silicate material are so acidified. Preferably, the compositions of the instant invention are calcined at less than 800 degrees Celsius, more preferably at from 100-500 degrees Celsius, and most preferably at from 100-300 degrees Celsius.
The silica gel composition of the instant invention can be contacted with a metaUocene polymerization catalyst to produce a catalyst composition. MetaUocene polymerization catalysts are well known in the art and include derivatives of Group 3, 4, or Lanthanide metals which are in the +2, +3, or +4 formal oxidation state. Preferred compounds include metal complexes containing from 1 to 3 π-bonded anionic or neutral ligand groups, which may be cyclic or non-cyclic delocalized π-bonded anionic ligand groups. Exemplary of such π-bonded anionic ligand groups are conjugated or nonconjugated, cyclic or non-cyclic dienyl groups, allyl groups, boratabenzene groups, and arene groups. By the term "π-bonded" is meant that the ligand group is bonded to the transition metal by a sharing or donating of electrons from a partially delocalized π-bond.
Each atom in the delocalized π-bonded group may independently be substituted with a radical selected from the group consisting of hydrogen, halogen, hydrocarbyl, halohydrocarbyl, hydrocarbyl-substituted metalloid radicals wherein the metalloid is selected from Group 14 of the Periodic Table of the Elements, and such hydrocarbyl- or hydrocarbyl-substituted metalloid radicals further substituted with a Group 15 or 16 hetero atom containing moiety. Included within the term "hydrocarbyl" are Cι_20 straight, branched and cyclic alkyl radicals, C5.20 aromatic radicals, C7.20 alkyl-substituted aromatic radicals, and C7.20 aryl-substituted alkyl radicals. In addition two or more such radicals may together form a fused ring system, including partially or fully hydrogenated
fused ring systems, or they may form a metallocycle with the metal. Suitable hydrocarbyl- substituted organometalloid radicals include mono-, di- and tri-substituted organometalloid radicals of Group 14 elements wherein each of the hydrocarbyl groups contains from 1 to 20 carbon atoms. Examples of suitable hydrocarbyl-substituted organometalloid radicals include trimethylsilyl, triethylsilyl, ethyldimethylsilyl, methyldiethylsih l, triphenylgermyl, and trimethylgermyl groups. Examples of Group 15 or 16 hetero atom containing moieties include amine, phosphine, ether or thioether moieties or divalent derivatives thereof, e. g., amide, phosphide, ether or thioether groups bonded to the transition metal or Lanthanide metal, and bonded to the hydrocarbyl group or to the hydrocarbyl- substituted metalloid containing group.
Examples of suitable anionic, delocalized π-bonded groups include cyclopentadienyl, indenyl, fluorenyl, tetrahydroindenyl, tetrahydrofluorenyl, octahydrofluorenyl, pentadienyl, cyclohexadienyl, dihydroanthracenyl, hexahydroanthracenyl, decahydroanthracenyl groups, and boratabenzene groups, as well as Ci-io hydrocarbyl-substituted or CMQ hydrocarbyl-substituted silyl substituted derivatives thereof. Preferred anionic delocalized π-bonded groups are cyclopentadienyl, pentamethylcyclopentadienyl, tetramethylcyclopentadienyl, tetramethylsilylcyclo- pentadienyl, indenyl, 2,3-dimethylindenyl, fluorenyl, 2-methylindenyl, 2-methyl-4- phenylindenyl, tetrahydrofluorenyl, octahydrofluorenyl, and tetrahydroindenyl.
The boratabenzenes are anionic ligands which are boron containing analogues to benzene. They are previously known in the art having been described by G. Herberich, et al., in Organometallics. 14,1 , 471-480 (1995). Preferred boratabenzenes correspond to the formula:
wherein R" is selected from the group consisting of hydrocarbyl, silyl, or germyl, said R" having up to 20 non-hydrogen atoms. In complexes involving divalent derivatives of such delocalized π-bonded groups one atom thereof is bonded by means of a covalent bond or a
covalently bonded divalent group to another atom of the complex thereby forming a bridged system.
A suitable class of catalysts are transition metal complexes corresponding to the formula: K']< Z'mLιXp, or a dimer thereof
wherein:
K' is an anionic group containing delocalized π-electrons through which K' is bound to M, said K' group containing up to 50 atoms not counting hydrogen atoms, optionally two K' groups may be joined together forming a bridged structure, and further optionally one K' may be bound to Z';
M is a metal of Group 4 of the Periodic Table of the Elements in the +2, +3 or +4 formal oxidation state;
Z' is an optional, divalent substituent of up to 50 non-hydrogen atoms that together with K forms a metallocycle with M; L is an optional neutral ligand having up to 20 non-hydrogen atoms;
X each occurrence is a monovalent, anionic moiety having up to 40 non- hydrogen atoms, optionally, two X groups may be covalently bound together forming a divalent dianionic moiety having both valences bound to M, or, optionally 2 X groups may be covalently bound together to form a neutral, conjugated or nonconjugated diene that is bound to M by means of delocalized π-electrons (whereupon M is in the +2 oxidation state), or further optionally one or more X and one or more L groups may be bonded together thereby forming a moiety that is both covalently bound to M and coordinated thereto by means of Lewis base functionality; k is 0, 1 or 2; m is 0 or 1 ;
1 is a number from 0 to 3; p is an integer from 0 to 3; and
the sum, k+m+p, is equal to the formal oxidation state of M, except when 2 X groups together form a neutral conjugated or non-conjugated diene that is bound to M via delocalized π-electrons, in which case the sum k+m is equal to the formal oxidation state of M. Preferred complexes include those containing either one or two K' groups.
The latter complexes include those containing a bridging group linking the two K' groups. Preferred bridging groups are those corresponding to the formula (ER'2)χ wherein E is silicon, germanium, tin, or carbon, R' independently each occurrence is hydrogen or a group selected from silyl, hydrocarbyl, hydrocarbyloxy and combinations thereof, said R' having up to 30 carbon or silicon atoms, and x is 1 to 8. Preferably, R' independently each occurrence is methyl, ethyl, propyl, benzyl, tert-butyl, phenyl, methoxy, ethoxy or phenoxy.
Examples of the complexes containing two K' groups are compounds corresponding to the formula:
wherein:
M is titanium, zirconium or hafnium, preferably zirconium or hafnium, in the +2 or +4 formal oxidation state;
R3 in each occurrence independently is selected from the group consisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo and combinations thereof, said R having up to 20 non-hydrogen atoms, or adjacent R3 groups together form a divalent derivative (that is, a hydrocarbadiyl, siladiyl or germadiyl group) thereby forming a fused ring system, and
X" independently each occurrence is an anionic ligand group of up to 40 non- hydrogen atoms, or two X" groups together form a divalent anionic ligand group of up to 40 non-hydrogen atoms or together are a conjugated diene having from 4 to 30 non-hydrogen
atoms bound by means of delocalized π-electrons to M, whereupon M is in the +2 formal oxidation state, and
R', E and x are as previously defined.
The foregoing metal complexes are especially suited for the preparation of polymers having stereoregular molecular structure. In such capacity it is preferred that the complex possesses Cs or C2 symmetry or possesses a chiral, stereorigid structure. Examples of the first type are compounds possessing different delocalized π-bonded ligand groups, such as one cyclopentadienyl group and one fluorenyl group. Similar systems based on Ti(IV) or Zr(IV) were disclosed for preparation of syndiotactic olefin polymers in Ewen, et al., J. Am. Chem. Soc. 1 10, 6255-6256 (1980). Examples of chiral structures include rac bis-indenyl complexes. Similar systems based on Ti(rV) or Zr(IV) were disclosed for preparation of isotactic olefin polymers in Wild et al., J. Organomet. Chem., 232, 233-47, (1982).
Exemplary bridged ligands containing two π-bonded groups are: dimethylbis(cyclopentadienyl)silane, dimethylbis(tetramethylcyclopentadienyl)silane, dimethylbis(2-ethylcyclopentadien-l-yl)silane, dimethylbis(2-t-butylcyclopentadien-l- yl)silane, 2,2-bis(tetramethylcyclopentadienyl)propane, dimethylbis(inden- 1 -yl)silane, dimethylbis(tetrahydroinden- 1 -yl)silane, dimethylbis(fluoren- 1 -yl)silane, dimethylbis(tetrahydrofluoren- 1 -yl)silane, dimethylbis(2-methyl-4-phenylinden- 1 -yl)-silane, dimethylbis(2-methylinden- 1 -yl)silane, dimethyl(cyclopentadienyl)(fluoren- 1 -yl)silane, dimethyl(cyclopentadienyl)(octahydrofluoren-l-yl)silane, dimethyl(cyclopentadienyl)(tetrahydrofluoren-l-yl)silane, (1, 1 , 2, 2-tetramethy)-l, 2- bis(cyclopentadienyl)disilane, (1, 2-bis(cyclopentadienyl)ethane, and dimethyl(cyclopentadienyl)- 1 -(fluoren- 1 -yl)methane. Preferred X" groups are selected from hydride, hydrocarbyl, silyl, germyl, halohydrocarbyl, halosilyl, silylhydrocarbyl and aminohydrocarbyl groups, or two X" groups together form a divalent derivative of a conjugated diene or else together they form a neutral, π-bonded, conjugated diene. Most preferred X" groups are Ci _20 hydrocarbyl groups.
A further class of metal complexes utilized in the present invention corresponds to the preceding formula K'^MZ^LnXp, or a dimer thereof, wherein Z' is a divalent substituent of up to 50 non-hydrogen atoms that together with K' forms a metallocycle with M. Preferred divalent Z' substituents include groups containing up to 30 non- hydrogen atoms comprising at least one atom that is oxygen, sulfur, boron or a member of Group 14 of the Periodic Table of the Elements directly attached to K', and a different atom, selected from the group consisting of nitrogen, phosphorus, oxygen or sulfur that is covalently bonded to M. A preferred class of such Group 4 metal coordination complexes used according to the present invention corresponds to the formula:
wherein:
M is titanium or zirconium, preferably titanium in the +2, +3, or +4 formal oxidation state;
R3 in each occurrence independently is selected from the group consisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo and combinations thereof, said R having up to 20 non-hydrogen atoms, or adjacent R3 groups together form a divalent derivative (that is, a hydrocarbadiyl, siladiyl or germadiyl group) thereby forming a fused ring system, each X is a halo, hydrocarbyl, hydrocarbyloxy or silyl group, said group having up to 20 non-hydrogen atoms, or two X groups together form a neutral C5.30 conjugated diene or a divalent derivative thereof; Y is -O-, -S-, -NR'-, -PR'-; and
Z is SiR'2, CR'2, SiR'2SiR'2, CR'2CR'2, CR'=CR\ CR'2SiR'2, or GeR'2, wherein R' is as previously defined.
Illustrative Group 4 metal complexes that may be employed in the practice of the present invention include:
5 cyclopentadienyltitaniumtrimethyl, cyclopentadienyltitaniumtriethyl, cyclopentadienyltitaniumtriisopropyl, cyclopentadienyltitaniumtriphenyl, cyclopentadienyltitaniumtribenzyl, o cyclopentadienyltitanium-2,4-dimethylpentadienyl, cyclopentadienyltitanium-2,4-dimethylpentadienyl»triethylphosphine, cyclopentadienyltitanium-2,4-dimethylpentadienyl«trimethylphosphine, cyclopentadienyltitaniumdimethylmethoxide, cyclopentadienyltitaniumdimethylchloride, pentamethylcyclopentadienyltitaniumtrimethyl, 5 indenyltitaniumtrimethyl , indenyltitaniumtriethyl, indenyl titaniumtripropyl , indenyltitaniumtriphenyl, tetrahydroindenyltitaniumtribenzyl, o pentamethylcyclopentadienyltitaniumtriisopropyl, pentamethylcyclopentadienyltitaniumtribenzyl, pentamethylcyclopentadienyltitaniumdimethylmethoxide, pentamethylcyclopentadienyltitaniumdimethylchloride, bis(η5-2,4-dimethylpentadienyl)titanium, 5 bis(η5-2,4-dimethylpentadienyl)titanium«trimethylphosphine, bis(η5-2,4-dimethylpentadienyl)titanium«triethylphosphine, octahydrofluorenyltitaniumtrimethyl, tetrahydroindenyltitaniumtrimethyl, tetrahydrofluorenyltitaniumtrimethyl, o (tert-butylamido)( 1 , 1 -dimethyl-2,3,4,9, 10-η- 1 ,4,5,6,7,8- hexahydronaphthalenyl)dimethylsilanetitaniumdimethyl,
(tert-butylamido)(l ,l ,2,3-tetramethyl-2,3,4,9, 10-η-l ,4,5,6,7,8- hexahydronaphthalenyl)dimethylsilanetitaniumdimethyl, (tert-butylamido)(tetramethyl-η -cyclopentadienyl) dimethylsilanetitanium dibenzyl, (tert-butylamido)(tetramethyl-η -cyclopentadienyl)dimethylsilanetitanium dimethyl, 5 (tert-butylamido)(tetramethyl-η5-cyclopentadienyl)- 1 ,2-ethanediyltitanium dimethyl, (tert-butylamido)(tetramethyl-η5-indenyl)dimethylsilanetitanium dimethyl, (tert-butylamido)(tetramethyl-η5-cyclopentadienyl)dimethylsilane titanium (HI)
2-(dimethylamino)benzyl ; (tert-butylamido)(tetramethyl-η5-cyclopentadienyl)dimethylsilanetitanium (HI) allyl, l o (tert-butylamido)(tetramethyl-η5-cyclopentadienyl)dimethylsilanetitanium (HI) 2 ,4-dimethylpentadienyl , (tert-butylamido)(tetramethyl-η5-cyclopentadienyl)dimethylsilanetitanium (II)
1 ,4-diphenyl- 1 ,3-butadiene, (tert-butylamido)(tetramethyl-η5-cyclopentadienyl)dimethylsilanetitanium (II) 15 1 ,3-pentadiene,
(tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (II) 1 ,4-diphenyl- 1 ,3- butadiene, (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (II) 2,4-hexadiene, (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV) 2,3-dimethyl- 1 ,3- 0 butadiene,
(tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV) isoprene, (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV) 1 ,3-butadiene, (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (IV) 2,3-dimethyl- 1 ,3-butadiene, 5 (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (IV) isoprene (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (IV) dimethyl (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (IV) dibenzyl (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (IV) 1 ,3-butadiene, o (tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (II) 1 ,3-pentadiene,
(tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (II) 1 ,4-diphenyl- 1,3 -butadiene,
(tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (II) 1 ,3-pentadiene, (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV) dimethyl, (tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV) dibenzyl, (tert-butylamido)(2-methyl-4-phenylindenyl)dimethylsilanetitanium (II) 5 l,4-diphenyl-l,3-butadiene,
(tert-butylamido)(2-methyl-4-phenylindenyl)dimethylsilanetitanium (H) 1 ,3-pentadiene, (tert-butylamido)(2-methyl-4-phenylindenyl)dimethylsilanetitanium (II) 2,4-hexadiene, (tert-butylamido)(tetramethyl-η5-cyclopentadienyl)dimethyl-silanetitanium (IV)
1,3 -butadiene, l o (tert-butylamido)(tetramethyl-η5-cyclopentadienyl)dimethylsilanetitanium (IV)
2,3-dimethyl-l,3-butadiene, (tert-butylamido)(tetramethyl-η5-cyclopentadienyl)dimethylsilanetitanium (IV) isoprene, (tert-butylamido)(tetramethyl-η' -cyclopentadienyl)dimethyl-silanetitanium (II)
15 l,4-dibenzyl-l,3-butadiene,
(tert *t--bbuuttyyllaammiiddoo))((ttetramethyl-η5-cyclopentadienyl)dimethylsilanetitanium (II) 2,4-hexadiene,
(tert-butylamido)(tetramethyl-η -cyclopentadienyl)dimethyl-silanetitanium (II) 3-methyl- 1 ,3-pentadiene, 0 (tert-butylamido)(2,4-dimethylpentadien-3-yl)dimethylsilanetitaniumdimethyl, (tert-butylamido)(6,6-dimethylcyclohexadienyl)dimethylsilanetitaniumdimethyl, (tert-butylamido)(l ,l-dimethyl-2,3,4,9, 10-η-l, 4,5,6,7, 8-hexahydronaphthalen-4- yl)dimethylsilanetitaniumdimethyl, (tert-butylamido)(l,l,2,3-tetramethyl-2,3,4,9,10-η-l,4,5,6,7,8-hexahydronaphthalen-4- 5 yl)dimethylsilanetitaniumdimethyl
(tert-butylamido)(tetramethyl-η5-cyclopentadienyl methylphenylsilanetitanium (IV) dimethyl,
(ter tt--bbuuttyyllaammiido)(tetramethyl-η5-cyclopentadienyl methylphenylsilanetitanium (It) 1 ,4-diphenyl- 1 ,3-butadiene, o 1 -(t :eertrt--bbuuttyyllaammiiddco)-2-(tetramethyl-η 5-cyclopentadienyl)ethanediyl titanium (IV) dimethyl, and
l-(tert-butylamido)-2-(tetramethyl-η5-cyclopentadienyl)ethanediyl- titanium (II) 1,4- diphenyl- 1 ,3-butadiene.
Complexes containing two K' groups including bridged complexes suitable for use in the present invention include:
5 bis(cyclopentadienyl)zirconiumdimethyl, bis(cyclopentadienyl)zirconium dibenzyl, bis(cyclopentadienyl)zirconium methyl benzyl, bis(cyclopentadienyl)zirconium methyl phenyl, bis(cyclopentadienyl)zirconiumdiphenyl, i o bis(cyclopentadienyl)titanium-allyl, bis(cyclopentadienyl)zirconiummethylmethoxide, bis(cyclopentadienyl)zirconiummethylchloride, bis(pentamethylcyclopentadienyl)zirconiumdimethyl, bis(pentamethylcyclopentadienyl)titaniumdimethyl, 15 bis(indenyl)zirconiumdimethyl, indenylfluorenylzirconiumdimethyl, bis(indenyl)zirconiummethyl(2-(dimethylamino)benzyl), bis(indenyl)zirconiummethyltrimethylsilyl, bis(tetrahydroindenyl)zirconiummethyltrimethylsilyl, 2 o bis(pentamethylcyclopentadienyl)zirconiummethylbenzyl, bis(pentamethylcyclopentadienyl)zirconiumdibenzyl, bis(pentamethylcyclopentadienyl)zirconiummethylmethoxide, bis(pentamethylcyclopentadienyl)zirconiummethylchloride, bis(methylethylcyclopentadienyl)zirconiumdimethyl, 5 bis(butylcyclopentadienyl)zirconiumdibenzyl, bis(t-butylcyclopentadienyl)zirconiumdimethyl, bis(ethyltetramethylcyclopentadienyl)zirconiumdimethyl, bis(methylpropylcyclopentadienyl)zirconiumdibenzyl, bis(trimethylsilylcyclopentadienyl)zirconiumdibenzyl,
3 o dimethylsilyl-bis(cyclopentadienyl)zirconiumdimethyl, dimethylsilyl-bis(tetramethylcyclopentadienyl)titanium (IH) allyl dimethylsilyl-bis(t-butylcyclopentadienyl)zirconiumdichloride,
dimethylsilyl-bis(n-butylcyclopentadienyl)zirconiumdichloride, (methylene-bis(tetramethylcyclopentadienyl)titanium(III) 2-(dimethylamino)benzyl, (methylene-bis(n-butylcyclopentadienyl)titanium(III) 2-(dimethylamino)benzyl, dimethylsilyl-bis(indenyl)zirconiumbenzylchloride, 5 dimethylsilyl-bis(2-methylindenyl)zirconiumdimethyl, dimethylsilyl-bis(2-methyl-4-phenylindenyl)zirconiumdimethyl, dimethylsilyl-bis(2-methylindenyl)zirconium-l,4-diphenyl-l,3-butadiene, dimethylsilyl-bis(2-methyl-4-phenylindenyl)zirconium (II) 1 ,4-diphenyl- 1 ,3-butadiene, dimethylsilyl-bis(tetrahydroindenyl)zirconium(II) 1 ,4-diphenyl- 1 ,3-butadiene, o dimethylsilyl-bis(fluorenyl)zirconiummethylchloride, dimethylsilyl-bis(tetrahydrofluorenyl)zirconium bis(trimethylsilyl), (isopropylidene)(cyclopentadienyl)(fluorenyl)zirconiumdibenzyl, and dimethylsilyl(tetramethylcyclopentadienyl)(fluorenyl)zirconium dimethyl.
Other acid activated polymerization catalysts (including Ziegler-Natta 5 catalysts and Brookhart Gibson catalysts) will, of course, be apparent to those skilled in the art and are to be included within the scope of the instant invention as if they were a metaUocene polymerization catalyst. The relative amount of metaUocene polymerization catalyst is the same in the instant invention as in the prior art of metaUocene catalysts and depends on the specific catalyst used. It should be understood that the instant invention may 0 be used for any polymerization process including solution, slurry and gas phase polymerization and that any polymerization catalyst may be used which is acid activated.
When an olefin is contacted with the catalyst composition of the instant invention, the olefin polymerizes to form a polymer. The acid component of the acidified layered silicate material activates the metaUocene polymerization catalyst to produce the 5 polymer. Preferably, before contacting the acidified cation exchanging layered silicate material with the metaUocene polymerization catalyst, the residual hydroxyl or other reactive functionality of the acid treated cation exchanging layered silicate material is capped or reacted with a reactive material, especially a Lewis acid. Preferred Lewis acids include trialkyl aluminum compounds having from 1 to 10 carbons in each alkyl group. o Preferably in the particle size of the silica gel composition of the instant invention is in the range of from ten to fifty micrometers (and more preferably from ten to
thirty micrometers). Such compositions can be prepared, for example, by one of the following four methods.
The first method comprises two steps. The first step is to mix a cation exchanging layered silicate material with an acid (such as hydrochloric acid or sulfuric acid) and a alkaline metal silicate in solution (such as sodium silicate solution) so that the cation exchanging layered silicate material is acidified and so that the alkaline metal silicate precipitates as silica hydrogel. It should be understood throughout this specification and in the claims hereof that the term "silica hydrogel" comprises a silica sol. The second step is to process the silica hydrogel to produce a silica gel composition having the acidified cation exchanging layered silicate material dispersed therewith, the composition having more than one percent acidified cation exchanging layered silicate material and more than one percent silica gel.
The silica gel composition of the preceding paragraph may then be contacted with a metaUocene polymerization catalyst to produce a catalyst composition. Such a catalyst composition may then be used to make a polymer by contacting the catalyst composition with an olefin to produce the polymer.
The second method comprises three steps. The first step is to mix a mixture of silica gel and water to produce a silica gel slurry. The second step is to mix an acidified cation exchanging layered silicate material with the silica gel slurry to produce a mixed slurry. The third step is to spray dry the mixed slurry to produce the silica gel composition, the silica gel composition having more than one percent acidified cation exchanging layered silicate material and more than one percent silica gel. It should be understood that spray drying is preferred but that any drying technique can be used as long as the final product is usable. The silica gel composition of the preceding paragraph may then be contacted with a metaUocene polymerization catalyst to produce a catalyst composition. Such a catalyst composition may then be used to make a polymer by contacting the catalyst composition with an olefin to produce a polymer.
The third method comprises three steps. The first step is to mix an alkaline metal silicate solution with an acid to produce an acidic silica hydrogel slurry. The second step is to mix the acidic silica hydrogel slurry with a cation exchanging layered silicate
material to produce a slurry of acidified cation exchanging layered silicate material and silica hydrogel. The third step is to dry the slurry of acidified cation exchanging layered silicate material and silica hydrogel to produce the silica gel composition, the silica gel composition having more than one percent acidified cation exchanging layered silicate material and more than one percent silica gel.
The silica gel composition of the preceding paragraph may then be contacted with a metaUocene polymerization catalyst to produce a catalyst composition. Such a catalyst composition may then be used to make a polymer by contacting the catalyst composition with an olefin to produce a polymer. The fourth method comprises two steps. The first step is to mix silica gel particles, particles of cation exchanging layered silicate material, an acid and water, the silica gel having pores therein, at least a portion of the pores of the silica gel being large enough to allow the entry of at least a portion of the particles of acidified cation exchanging layered silicate material into the pores of the silica gel. The second step is to dry the silica gel particles to produce the silica gel composition, the silica gel composition having more than one percent acidified cation exchanging layered silicate material and more than one percent silica gel having more than one percent acidified cation exchanging layered silicate material and more than one percent silica gel.
The silica gel composition of the preceding paragraph may then be contacted with a metaUocene polymerization catalyst to produce a catalyst composition. Such a catalyst composition may then be used to make a polymer by contacting the catalyst composition with an olefin to produce a polymer.
Preferably, the olefin used in the instant invention is selected from the group of olefins having from two to ten carbon atoms. Such olefins include, for example, styrene, divinylbenzene, norborene, ethylene, propylene, octene, butadiene and mixtures thereof. Thus, the polymer product of or by way of the instant invention may be, for example, a rubber, a thermoplastic elastomer, polyethylene and polypropylene.
GENERAL COMMENTS ON EXAMPLES 1-7
Unless otherwise specified, all reactions are carried out in a nitrogen-filled glove box using standard techniques. Solvents are purified of oxygen, water, and oxygenates by a nitrogen purge followed by flow through a 12 inch column filled with heat treated (250 °C overnight) alumina.
MetaUocene catalyst (t-butylamido)(tetramethyl-η5- cyclopentadienyl)dimethylsilanetitanium (II) η4-3-methyl-l,3-pentadiene (CGCTi) is prepared according to US Patent 5,470,933 example A2. MetaUocene catalyst rac- dimethylsilyl-bis-(2-methyl-4-phenyl-η5-indenyl) zirconium (η4-trans-trans- 1 ,4-diphenyl- 1,3 -butadiene) (DOCZr) is prepared according to US Patent 5,972,822 example 15.
The layered silicate/silica gel compositions of the instant invention are prepared by premixing fully acid exchanged montmorillonite with polyolefin grade silica gel in the appropriate ratios followed by spray drying. Such compositions are prepared having montmorillonite amounts ranging from 10 percent to 50 percent by weight of the composition. All other reagents were obtained from Aldrich Chemical and used without further purification.
EXAMPLE 1
A 200 g sample of a silica gel/montmorillonite composition with nominal 40 μm particle size is calcined in air at 250 °C for 12 hours. To 5.00 g of the calcined material slurried in 35 mL toluene under nitrogen is added 5 mL of a 1.9M solution of triethyl aluminum in toluene. The mixture is agitated on a mechanical shaker for 30 minutes. At this time the solids are collected on a fritted funnel, washed once with 30 mL toluene, once with 30 mL hexane, and dried in vacuo. To 3.00 g of the treated material slurried in 40 mL toluene is added 0.085 g of DOCZr as a crystalline solid. Following addition , the slurry is shaken for 1 hour. The solids are collected on a fritted funnel and washed with toluene until the filtrate is clear. The solids are next washed with hexane and dried in vacuo. Catalysts are prepared on supports having 10 percent montmorillonite
(Catalyst A), 20 percent montmorillonite (Catalyst B) and montmorillonite percent (Catalyst
C).
EXAMPLE 2
A stirred 4.0 L reactor is charged with 1800 g of hexane and heated to the reaction temperature of 70°C. Ethylene is added to the reactor in an amount sufficient to bring the total pressure to the desired operating level of 1.3 MPa (190 psi). Samples of the catalysts from Example 1 are then added to the reactor using nitrogen pressure. The reactor pressure is kept essentially constant by continually feeding ethylene on demand during the polymerization run while maintaining the reactor temperature at 70°C with a cooling jacket. After 60 minutes, the ethylene flow is discontinued, the reactor is vented, and the contents of the reactor are filtered to isolate the powdered polymeric product. The powder is dried in a vacuum oven. The efficiency and polymer yield results are given below.
EXAMPLE 3
A 200 g sample of a silica gel/montmorillonite composition of the instant invention with nominal 30 μm particle size and 20 percent montmorillonite is calcined in air at 250 °C for 12 hours. To 10.00 g of the calcined material slurried in 60 mL hexane under nitrogen is added 20 mL of a 1.9M solution of triethylaluminum in toluene. The mixture is agitated on a mechanical shaker for 3 hours. At this time the solids are collected on a fritted funnel, washed twice with 50 mL hexane, and dried in vacuo. To 5.00 g of the treated material slurried in 35 mL toluene is added 0.076 g of DOCZr as a crystalline solid.
Following addition , the slurry is shaken for 3 hours. The solids are collected on a fritted funnel and washed with toluene until the filtrate is clear. The solids are next washed with hexane and dried in vacuo to produce Catalyst D.
EXAMPLE 4
A stirred 2.0 L reactor is purged with nitrogen for one hour while heating the jacket to 100 °C. The reactor is cooled to 30 °C and the catalyst charge (0.23 g Catalyst D) is injected with nitrogen pressure from a bomb. The cylinder is rinsed once with -50 mL 0 hexane. Next, hydrogen is introduced into the reactor to a delta psi of 23, and 500 g of liquid propylene are added. The agitator is turned on, and the reactor is held at 30 °C for 10 minutes. Next, the reactor is heated rapidly (-10 7min) to 70 C and run for an additional hour while controlling the reactor temperature at 70 C. After an hour the reactor is cooled to ambient temperature, depressured, and the product is recovered. The yield of polypropylene 5 is 75 g correspond to an efficiency of 326 grams of polypropylene per gram of Catalyst D.
EXAMPLE 5
The 50 percent montmorillonite/silica gel material of the instant invention is calcined and treated with TEA as described in Example 1. To 3.00 g of this material o slurried in 20 mL hexane is added 0.090 mL of a 0.156 M solution of CGCTi in heptane.
The slurry is shaken for 4 hours. At this time, the solids are collected on a fritted funnel, washed once with 20 mL toluene, once with 20 mL hexanes, and dried in vacuo to prepare Catalyst E.
5 EXAMPLE 6
The 20 percent montmorillonite/silica gel material of the instant invention is calcined and treated with TEA as described in Example 1. To 2.07 g of this material slurried in 15 mL hexane is added 0.380 mL of a 0.157 M solution of CGCTi in heptane. The slurry is agitated for 3 hours. At this time, the solids are collected on a fritted funnel, o washed twice with 20 mL hexanes, and dried in vacuo to produce Catalyst F.
EXAMPLE 7
Catalysts E and F are evaluated for ethylene polymerization in a slurry polymerization process as described in Example 2. The white polyethylene powders obtained have good morphology and good bulk density.
EXAMPLE 8
To 0.5 g of calcined 50 percent montmorillonite silica gel composition of the instant invention havig a nominal 30 μm particle size is slurried in 40 ml of toluene under argon. Then 4 mL of neat triethylaluminum is added. The mixture is stirred for 2 hours. At this time the solids are collected on a fritted funnel and washed twice with 50 mL toluene. One half gram of the solids are slurried in 35 mL toluene and 5 ml of 1.25 mM of DOCZr solution is added. Following this addition , the slurry is stirred for 1 hour. The solids are collected on a fritted funnel and washed with toluene until the filtrate is clear. The solids were then dried in vacuo to produce Catalyst G.
EXAMPLE 9
A stirred 2.0 L reactor is purged with nitrogen for one hour while heating the jacket to 100 °C. The reactor is cooled to 30 °C and the catalyst charge (40 mg Catalyst G) is injected with nitrogen pressure from a bomb. The cylinder is rinsed once with -50 mL hexane. Next, hydrogen is introduced into the reactor to a delta psi of 40 from a 50 ml shot tank, and 500 g of liquid propylene is added. The agitator is turned on, and the reactor is held at 25 °C for 5 minutes. Next, the reactor is heated rapidly (-10 7min) to 70 °C and run for a total 40 mins while controlling the reactor temperature at 70 °C. After 40 minutes, the reactor is cooled to ambient temperature, depressured, and the product is recovered. The yield of polypropylene is 34 g correspond to an efficiency of 850 gPP/gCat. The white polypropylene powder produced has good morphology.
EXAMPLE 10
A 10 g sample of a 20 percent montmorillonite silica gel composition of the instant invention having a nominal 30 μm particle size is calcined in air at 250 °C for 4 hours. To 0.5 g of the calcined material slurried in 40 ml of toluene under argon is added 4 mL of neat triethylaluminum. The mixture is stirred for 2 hours. At this time the solids are collected on a fritted funnel and washed twice with 50 mL toluene. To 0.50 g of the treated material slurried in 35 mL toluene is added 5 ml of 1.25 mM of DOCZr solution. Following this addition, the slurry is for 1 hour. The solids are collected on a fritted funnel and washed with toluene until the filtrate is clear. The solids are then dried in vacuo to produce Catalyst H.
EXAMPLE 11
A stirred 2.0 L reactor is purged with nitrogen for one hour while heating the jacket to 100 °C. The reactor is cooled to 30 °C and the catalyst charge (40 mg Catalyst H) is injected with nitrogen pressure from a bomb. The cylinder is rinsed once with -50 mL hexane. Next, hydrogen is introduced into the reactor to a delta psi of 40 from a 50 ml shot tank, and 500 g of liquid propylene is added. The agitator is turned on, and the reactor is held at 25 °C for 5 minutes. Next, the reactor is heated rapidly (-10 7min) to 70 C and run for a total 40 mins while controlling the reactor temperature at 70 C. After 40 minutes, the reactor is cooled to ambient temperature, depressured, and the product is recovered. The yield of polypropylene is 41 g correspond to an efficiency of 1025 gPP/gCat. The white polypropylene powder produced has good morphology.