DE4130429A1 - METHOD FOR PRODUCING MULTI-PHASE BLOCK COPOLYMERISATS BASED ON ALK-1-ENEN - Google Patents

Abstract

The invention concerns a method of producing multi-phase block copolymers, the method being characterized in that, in the gas phase, in the presence of a metalocene catalyst system at temperatures of -50 to +300 DEG C and pressures of 1 to 1000 bar: a) as a first step, 45 to 95 % by wt. of a polymer matrix (A) comprising an alk-1-ene homopolymer or copolymer with a comonomer content of up to 10 % by wt. relative to the matrix (A) is produced and b) as a second step, in the presence of the matrix (A) obtained in step (a), b1) o.5 to 97 % by wt. of at least one alk-1-ene having at least 3 C-atoms and b2) 3 to 99.5 % by wt. of ethylene is reacted to give 5 to 55 % by wt. of a copolymer phase (B).

Description

The present invention relates to methods of making more phase block copolymers.

In addition, the invention relates to the use of the more so obtained phase block copolymers for the production of fibers, films and Moldings and the fibers, foils and moldings available here per from the multiphase block copolymers thus obtained as we substantial component.

Multi-phase block copolymers are due to their properties fils widely used, for example in vehicle construction, in the manufacture of impact-modified everyday items such as Hard case or plastic storage containers and for manufacturing of office foils.

Copolymers are known from DE-A 38 27 565 and DE-A 40 01 157 the base of propylene and ethylene known with titanium carrier kata lysators are manufactured. However, these copolymers have one broad molecular weight distribution, which from processing technology reasons is undesirable.

EP-A 4 33 990 describes a process for the production of Polypro pylene molding compositions, with a metallocene catalyst for polymerization was used and in the first stage of the two-step process a crystalline propylene polymer made in liquid monomer has been.

However, this process requires a complex intermediate relaxation when transferring the polymer into the second reactor and, in addition, the C ₂ content is limited in the first stage, which means that the monomer mixture must be liquid.

The object of the invention was therefore to overcome this disadvantage sided.  

Accordingly, a method for producing multiphase block co found polymers, where in the presence of a metallocene catalyst sator systems in the gas phase at temperatures from -50 to 300 ° C and Pressures from 1 to 1000 bar

• a) in a first stage 45 to 95 wt .-% of a matrix A) from one Alk-1-ene homo- or copolymer with a comonomer content of up to 10 wt .-%, based on the matrix A) and
• b) in a second stage in the presence of the matrix A) prepared according to a)
  • b ₁ ) 0.5 to 97% by weight of at least one alk-1-ene having at least 3 carbon atoms
• and
  • b ₂ ) 3 to 99.5% by weight of ethylene
• to 5 to 55 wt .-% of a copolymer phase B).

Furthermore, the use of the multiphase block co polymers for the production of fibers, films and moldings as well the fibers, films and moldings available here were found.

The multiphase block copolymers 45 contain component A) up to 95% by weight, preferably 55 to 90% by weight, of a matrix of an alk-1-ene Homopolymers or copolymers with a comonomer content of up to 10% by weight, preferably up to 4% by weight, based on the matrix.

Of the alk-1-enes, preference is given to those which have 3 to 5 carbon atoms exhibit, especially propylene. As comonomers are alkenes with 2 to To name 10 carbon atoms, especially alk-1-enes. In the preferred case, egg ner matrix of propylene copolymer are used as comonomers for example as ethylene, butenes, pentenes, hexenes, heptenes, octenes or their Mi. Schungen used, especially ethylene and but-1-ene. Especially however, propylene homopolymers are preferred.

The multiphase block copolymers 5 to contain component B) 55% by weight, preferably 10 to 45% by weight, of a copolymer phase out

• b ₁ ) 0.5 to 97% by weight, preferably 35 to 90% by weight, in particular 45 to 80% by weight, of at least one alk-1-ene having at least 3 carbon atoms
• b ₂ ) 3 to 99.5% by weight, preferably 10 to 65% by weight, in particular 20 to 55% by weight of ethylene.

The alk-1-enes with at least 3 C atoms used as component b ₁ ) are, for example, C ₃ - to C ₁₀ -alk-1-enes, preferably propylene, but-1-ene, pent-1-ene, hexane 1-ene, hept-1-ene and oct-1-ene. Particularly preferred is propylene, which can also be used in mixtures with C ₄ - to C ₁₀ -alk-1-enes, for example with but-1-enes.

The multiphase block copolymers can also be used as a component C) a copolymer phase different from B), built up from

• c ₁ ) 20.1 to 99.9% by weight, preferably 60 to 99% by weight, of at least one alk-1-ene having at least 3 C atoms
• c ₂ ) 0.1 to 79.9% by weight, preferably 1 to 40% by weight, of ethylene, the amount of b ₂ ) being greater than that of c ₂ ).

For component c ₁ ) the above applies to component b ₁ ) Ge, which is referred to here to avoid repetition.

If component C) ent in the multi-phase block copolymers hold, so in an amount of 0.1 to 50 wt .-%, preferably 0.1 to 20% by weight, the sum of components A), B) and C) 100% by weight does not exceed.

However, multiphase block copolymers are preferred, which consist of the Components A) and B) exist.

The multi-phase block copolymers are by reaction in counter were obtained from metallocene catalyst systems.

Suitable metallocene catalyst systems contain, as active constituents, inter alia a complex compound of metals of the IV and V. In addition to the periodic table, in particular titanium, zirconium, hafnium, vanadium, niobium or tantalum. Complex compounds are preferably used in which the metal atom is connected via n-bonds to unsaturated cyclic hydrocarbon atoms, for example cyclopentadienyl, fluorenyl or indenyl groups. Furthermore, the preferred complex compounds are characterized in that the metal atom with other ligands, in particular with fluorine, chlorine, bromine, iodine or a C ₁ - to C ₈ -alkyl, for example a methyl, ethyl, propyl or Butyl group, can be linked. Particularly suitable complex compounds contain chlorine or bromine in particular.

For example, EP-A 1 29 368, EP-A 4 07 870, EP-A 4 13 326, EP-A 3 99 347 and DE-A 39 29 693, in which suitable metallocene catalyst systems are described.

Metallocene catalyst systems which have proven to be preferred are as active ingredients

• a) a metallocene complex of the general formula I in which the substituents have the following meaning:
  R¹ to R⁸ are hydrogen, C₁ to C₁₀ alkyl, 5- to 7-membered cycloalkyl, which in turn can carry a C₁ to C₆ alkyl as a substituent, C₆ to C₁₅ aryl or arylalkyl, where appropriate also two adjacent radicals R⁴ and R¹, R¹ and R², R² and R³, R⁸ and R⁵, R⁵ and R⁶ or R⁶ and R⁷ together can represent unsaturated cyclic groups containing 4 to 15 carbon atoms,
  R⁹ C₁ to C₈ alkyl, C₃ to C₁₀ cycloalkyl, C₆ to C₁₀ aryl,
  Titanium, zirconium, hafnium, vanadium, niobium, tantalum, lanthanide,
  Y silicon, germanium, tin, sulfur, carbon,
  X is hydrogen, fluorine, chlorine, bromine, iodine, C₁ to C₁₀ alkyl, C₁ to C₁₀ alkoxy
  and n represents the numbers 0, 1 or 2,
• b) and an open-chain or cyclic alumoxane compound of the general formula II or III where R¹⁰ is a C₁ to C₁₀ alkyl group and m is a number from 5 to 30,

contain.

In the metallocene complexes of the general formula I are those preferred where

R¹ and R⁵ are the same and represent hydrogen or C₁ to C₁₀ alkyl groups,
R⁴ and R⁸ are the same and represent hydrogen, a methyl, ethyl, iso-propyl or tert-butyl group
R², R³, R⁶ and R⁷ the meaning
R³ and R⁷ C₁ to C₄ alkyl
R² and R⁶ are hydrogen
have or two adjacent radicals R² and R³ and R⁶ and R⁷ together represent unsaturated cyclic groups containing 4 to 12 carbon atoms,
R⁹ for C₁ to C₈ alkyl,
M for zirconium or hafnium,
Y for silicon, sulfur or carbon and
X represents chlorine or bromine.

Examples of particularly suitable complex compounds include a.

Dimethylsilanediylbis (-3-tert.butyl-5-methylcyclopentadienyl) zirconium dichloride,
Diethylsilanediylbis (-3-tert.butyl-5-methylcyclopentadienyl) zirconium mdichloride,
Methylethylsilanediylbis (-3-tert.butyl-5-methylcyclopentadienyl) zirk-onium dichloride,
Dimethylsilanediylbis (-3-tert.butyl-5-ethylcyclopentadienyl) zirconium mdichloride,
Dimethylsilanediylbis (-3-tert.butyl-5-methylcyclopentadienyl) dimeth-yl zirconium,
Dimethylsilanediylbis (-2-methylindenyl) zirconium dichloride,
Diethylsilanediylbis (-2-methylindenyl) zirconium dichloride,
Dimethylsilanediylbis (-2-ethylindenyl) zirconium dichloride,
Dimethylsilanediylbis (-2-isopropylindenyl) zirconium dichloride,
Dimethylsilanediylbis (-2-tert-butylindenyl) zirconium dichloride,
Diethylsilanediylbis (-2-methylindenyl) zirconium dibromide,
Dimethyl sulfide bis (-2-methylindenyl) zirconium dichloride,
Dimethylsilanediylbis (-2-methyl-5-methylcyclopentadienyl) zirconium di-chloride,
Dimethylsilanediylbis (-2-methyl-5-ethylcyclopentadienyl) zirconium dicloride,
Dimethylsilanediylbis (-2-ethyl-5-isopropylcyclopentadienyl) zirconium dichloride,
Dimethylsilanediylbis (-2-methylindenyl) zirconium dichloride,
Dimethylsilanediylbis (-2-methylbenzindenyl) zirconium dichloride and
Dimethylsilanediylbis (-2-methylindenyl) hafnium dichloride.

Mixtures of different metallocene complexes can also be used be set. The synthesis of such complex compounds can according to known methods take place, the implementation of the corresponding substituted, cyclic hydrocarbon anions with halides of titanium, zirconium, hafnium, vanadium, niobium or tantalum, preferred is. Examples of corresponding manufacturing processes include. a. in the Journal of Organometallic Chemistry, 369 (1989), 359-370.

In addition to the complex compound, the metallocene catalyst systems generally also contain oligomeric alumoxane compounds of the general formula II or III, where R ^{10 is} preferably methyl or ethyl groups and m is preferably a number from 10 to 25.

These oligomeric alumoxane compounds are usually produced by reacting a solution of trialkyl aluminum with What ser and is u. a. in EP-A 2 84 708 and US-A 47 94 096 ben.  

As a rule, the oligomeric alumoxane compounds obtained are gene as mixtures of different lengths, both linear and cyclic shear chain molecules, so that m is to be regarded as the mean. The Alumoxane compound can also trialkyl aluminum compounds contain, whose alkyl groups each have 1 to 8 carbon atoms, at for example trimethyl, triethyl or methyl diethyl aluminum.

It has proven to be advantageous to use the complex compound of metals of IV and V subgroup of the periodic table and the oligomeric alumoxane compound in such amounts that the atomic ratio between aluminum from the oligomeric alumoxane compound and the transition metal from the complex compound of metals IV. And V. Subgroup of the periodic table is in the range from 10: 1 to 10 ⁶ : 1, in particular in the range from 10: 1 to 10 ⁴ : 1.

In the process according to the invention for the production of multiphase Block copolymers are now in the presence of a metallocene catalyst gate systems in the gas phase at temperatures from -50 to 300 ° C and pressure from 1 to 1000 bar in a first stage, component A) forming monomers implemented, in a second stage in Anwe The component A) obtained in this way forms component B) the monomers are reacted and, if necessary, in another Stage that follows the first or second stage is preferred however, to the second stage, the monomers forming component C) implemented.

The metallocene catalyst system once selected is preferred in al len reaction levels maintained.

The process can be carried out in the usual manner, for the polymerization of Alk-1-enes reactors used either batchwise or preferably be carried out continuously. Suitable reactors include a. con continuously operated stirred kettles, usually using a stirred kettle cascade sets in. For the reaction in the gas phase contain the reak goals in general a fixed bed made of finely divided polymer, which is usually kept in motion by stirring.

Before the polymerization, the complex compound of metal is first len the IV. and V. subgroup of the periodic table with the oligomer Alumoxanverbindung mixed, which results in an activated catalytic converter door system forms. The duration of this activation step is usual Usually 1 to 120 minutes, preferably 10 to 100 minutes. The Ver Mixing is preferably carried out in such a way that the Complex compound with a solution of the oligomeric alumoxane compound  in an inert solvent, for example in benzene, toluene, He xan, heptane or their mixtures, at temperatures from 0 to 50 ° C in Brings contact.

The solution available can then be placed on a finely divided Polymer are applied. In a first step, the finely divided polymer with the obtained from the activation step Chen solution from the oligomeric alumoxane compound and the complex ver bond combined and 1 to 120 minutes, especially 10 to 60 minutes ten, stirred at a temperature of 10 to 50 ° C for a long time. After that, in a second step removes the solvent by evaporation, so that a solid, supported catalyst system can be isolated. Preferably used for the preparation of the catalyst system finely divided polymers with an average grain size ver graduation from 0.01 to 1.0 mm, in particular from 0.1 to 0.5 mm.

In a first polymerization stage a), the monomers forming component A) are then reacted in the presence of the metallocene catalyst system, the molar ratio of aluminum to subgroup metal generally 10 ⁶ : 1 to 1: 1, preferably 10 ⁴ : 1 to 10 ² : 1 is. It has proven to be advantageous if oligomeric alumoxane compounds are added to the monomers forming component A) in an inert solvent. For the reaction in the gas phase there are pressures of 20 to 40 bar, preferably 25 to 35 bar, temperatures of 60 to 90 ° C, preferably 65 to 85 ° C and average residence times of 1 to 5 hours, preferably of 1.5 up to 4 hours. The ratio between the partial pressure of the alk-1-ene and the comonomer which may be present is preferably set to 10: 1 to 500: 1, in particular to 15: 1 to 100: 1.

A preferred method is that the solution is complex compound and oligomeric alumoxane compound in inert solvent is mixed with liquid monomers and at temperatures from 0 to 100 ° C, in particular from 20 to 30 ° C and pressures from 0.1 to 100 bar, in particular from 0.1 to 1 bar, 0.1 to 100 min, in particular 1 to Is stirred for 10 min. The liquid monomers are preferred here ren first with further oligomeric alumoxane compound and further in erten solvent and then the solution of complex compound and oligomeric alumoxane compound in inert solvent admitted. From the suspension of catalyst system thus obtained in liquid monomers the liquid monomer becomes at temperatures of 0  evaporated to 100 ° C and the first polymerization stage in the gas phase carried out.

After the reaction has ended, component A) together with discharged from the first polymerization stage and in introduced the second polymerization stage, where a mixture of mind Add at least one alk-1-ene with at least 3 carbon atoms and ethylene is merized. This is usually done at a pressure of 5 to 25 bar, preferably 7 to 20 bar, at a temperature of 30 to 80 ° C, preferably from 50 to 75 ° C and with a residence time of 15 to 240 minutes, preferably from 20 to 180 minutes.

In the particularly preferred case that propylene is used as component b ₁ ), the ratio of the partial pressures between propylene and ethylene is in the range from 0.5: 1 to 20: 1, in particular in the range from 0.5: 1 to 10: 1. In the event that a mixture of propylene and a C ₄ - to C ₁₀ -alk-1-ene and ethylene is copolymerized, the ratio of the partial pressures between ethylene and the C ₄ - to C ₁₀ -alk-1-ene is im Range from 2: 1 to 100: 1, especially in the range from 5: 1 to 50: 1.

To this copolymer from components A) and B) can now in egg ner third stage a further, different from component B) Co polymer phase C) are polymerized. Usually you work here at a pressure of 2 to 20 bar, preferably from 5 to 18 bar a temperature of 30 to 80 ° C, preferably from 50 to 75 ° C and at egg ner residence time from 15 to 240 minutes, preferably from 20 to 180 minutes ten.

In the particularly preferred case that propylene is used as component c ₁ ), the ratio of the partial pressures between propylene and ethylene is in the range from 0.05: 1 to 20: 1, in particular in the range from 0.05: 1 to 3: 1. In the event that a mixture of propylene and a C ₄ - to C ₁₀ -alk-1-ene and ethylene is copolymerized, the ratio of the partial pressures between ethylene and the C ₄ - to C ₁₀ -alk-1-ene is im Range from 0.5: 1 to 1000: 1, especially in the range from 5: 1 to 100: 1.

In the event that the polymerization of the copolymer phase C) to the first polymerization stage a) and then to this copolyme Risp from components A) and C) to add components B) the reaction conditions remain for the second and third Receive stage, only components B) and C) are exchanged.  

The molecular weight of the polymers obtainable here can be as usual Lich by adding regulators, especially hydrogen control be lated. It is also possible to use inert gases such as nitrogen or Argon to be used.

The average molecular weights (weight average) of the multiphase Blockco polymers are between 10,000 and 500,000, the melt flow indi ces between 0.1 to 100 g / 10 min, preferably between 0.2 to 10 g / 10 min, each measured according to DIN 53 735 at 230 ° C and 2.16 kg. The melt flow index corresponds to the amount of polymer that within 10 minutes from the test standard standardized according to DIN 53 735 direction at a temperature of 230 ° C and under a weight of 2.16 kg is pressed out. From a procedural point of view, it is excluded the advantage that the bulk densities of the from the second polymer discharged copolymers are not lower than that polymers obtained from the first polymerization stage, and that the bulk densities of the third stage, if any NEN copolymers are not lower than those from the second stage copolymers obtained.

Due to their good mechanical properties, the are suitable the block copolymers prepared according to the method u. a. for the production of foils, pipes, coverings, fibers, hollow bodies, Injection molded articles and molded parts for vehicle construction.

Examples Examples 1 and 2 Production of block copolymers from propylene and ethylene. example 1

9.7 mg of dimethylsilanediylbis (-3-tert.butyl-5-methylcyclopentadie nyl) zirconium dichloride

were dissolved in 6.22 ml of 1.6 molar methylaluminoxane / toluene solution and stirred for 15 minutes at room temperature (molar ratio Al: Zr = 500: 1). 4 l of liquid propylene were condensed into a 10 l steel autoclave and stirred with 18.7 ml of 1 molar methylaluminoxane / toluene solution for 2 minutes at room temperature and a pressure of 12 bar. The solution of dimethylsilanediyl bis (-3-tert-butyl-5-methyl-cyclopentadienyl) zirconium dichloride and methylaluminoxane in toluene was then added and the mixture was stirred at room temperature for 5 minutes. The liquid propylene was passed into the gaseous state and polymerized for 1.5 hours at 70 ° C. and 28 bar in the gas phase. Then propylene and ethylene were polymerized in a second polymerization stage. For this purpose, the pressure was released to 7.5 bar, increased to 15 bar with ethylene and then allowed to drop again to 9.5 bar. Propylene and ethylene were alternately polymerized in, so that a weight ratio of propylene (component b ₁ )) to ethylene (component b ₂ )) was 50 to 50. The reaction was carried out in the gas phase at 70 ° C. for 30 minutes.

Example 2

Analogously to Example 1, 8.9 mg of dimethylsilanediylbis (-3-tert.bu tyl-5-methyl-cyclopentadienyl) zirconium dichloride in 5.7 ml of 1,6-mola rer Methylaluminoxan / toluene solution dissolved and 15 minutes at room temperature temperature stirred (molar ratio Al: Zr = 500: 1). For this, 1 g Polypropylene semolina with a grain diameter of less than 0.125 mm given, this suspension is stirred for 30 minutes at room temperature and then the solvent evaporated in vacuo. Then 1.33 g this catalyst system to a mixture of 20 g of polypropylene and a suspension of 810 mg methylaluminoxane in 50 ml heptane in one Given 10 l steel autoclaves. The propylene was in at 70 ° C and 28 bar polymerized in the gas phase for 105 minutes.

This was followed by 25 minutes in a second polymerization stage long propylene and ethylene as described in Example 1 rized.

The compositions and properties of the multiphase block copoly merisates are compiled in the table.

The viscosity was determined using a Ubbelohde viscometer, the weight average M _w and the number average M _n by gel permeation chromatography and the melting point by DSC measurements (differential scanning calorimetry).

table

Claims (10)

1. A process for the preparation of multiphase block copolymers, characterized in that in the presence of a Metallocenkata lysatorsystems in the gas phase at temperatures from -50 to 300 ° C and pressures from 1 to 1000 bar

• a) in a first stage 45 to 95% by weight of a matrix A) from an alk-1-ene homo- or copolymer with a comonomer content of up to 10% by weight, based on the matrix A)) and
• b) in a second stage in the presence of the matrix A) prepared according to a)
  • b₁) 0.5 to 97 wt .-% of at least one alk-1-ene with at least 3 carbon atoms and
  • b₂) 3 to 99.5 wt .-% ethylene
• to 5 to 55 wt .-% of a copolymer phase B).

2. A process for the preparation of multiphase block copolymers according to claim 1, characterized in that

• c) in a further stage which follows stage a) or stage b),
  • c₁) 20.1 to 99.9 wt .-% of at least one alk-1-ene having at least 3 carbon atoms and
  • c₂) 0.1 to 79.9% by weight of ethylene,
    where the amount of b₂) is greater than that of c₂),

to 0.1 to 50% by weight of a copolymer phase C), the Sum of components A), B) and C) should not exceed 100% by weight tet. 3. A process for the preparation of multiphase block copolymers according to claim 1, characterized in that the multiphase block copolymers are composed of
45 to 95% by weight of a matrix A) made of propylene homopolymer and
5 to 55% by weight of a copolymer phase B) ₁ composed of b ₁ ) 45 to 80% by weight of propylene and
b ₂ ) 20 to 55% by weight of ethylene. 4. A process for the preparation of multiphase block copolymers according to claims 1 to 3, characterized in that the Me tallocene catalyst system as active ingredients

• a) a metallocene complex of the general formula I in which the substituents have the following meaning:
  R¹ to R⁸ are hydrogen, C₁ to C₁₀ alkyl, 4- to 7-membered cycloalkyl, which in turn can carry a C₁ to C₆ alkyl as a substituent, C₆ to C₁₅ aryl or arylalkyl, optionally also two adjacent radicals R wobei and R¹, ¹ and R², R² and R³, R⁸ and R⁵, R⁵ and R⁶ or R⁶ and R⁷ together can represent unsaturated cyclic groups containing 4 to 15 carbon atoms,
  R⁹ C₁ to C₈ alkyl, C₃ to C₁₀ cycloalkyl, C₆ to C₁₀ aryl,
  M titanium, zirconium, hafnium, vanadium, niobium, tantalum, lanthanide,
  Y silicon, germanium, tin, sulfur, carbon,
  X is hydrogen, fluorine, chlorine, bromine, iodine, C₁ to C₁₀ alkyl, C₁ to C₁₀ alkoxy
  and n represents the numbers 0, 1 or 2,
• b) and an open-chain or cyclic alumoxane compound of the general formula II or III where R ^{10 is} a C ₁ to C ₁₀ alkyl group and m is a number from 5 to 30,

contains. 5. A process for the preparation of multiphase block copolymers according to claim 4, characterized in that in the general formula I
R⁹ for C₁ to C₈ alkyl,
M for zirconium or hafnium,
Y for silicon, germanium or carbon and
X for chlorine
stands. 6. A process for the preparation of multiphase block copolymers according to claims 4 to 5, characterized in that in the general formula I
R¹ and R⁵ are the same and represent hydrogen or C₁ to C₁₀ alkyl groups,
R⁴ and R⁸ are the same and represent a methyl, ethyl, iso-propyl or tert-butyl group for hydrogen
R², R³, R⁶ and R⁷ the meaning
R³ and R⁷ C₁ to C₄ alkyl
R² and R⁶ are hydrogen
have or two adjacent radicals R² and R³ and R⁶ and R⁷ together represent unsaturated, 4 to 12 carbon atoms having cyclic groups. 7. Use of the multiphase obtained according to claims 1 to 6 gene block copolymers for the production of fibers, films and Molded articles. 8. Fibers, films and moldings, obtainable from those according to the An say 1 to 6 multiphase block copolymers obtained as essential component.