DE2214271C3 - Process for the production of high molecular weight, low pressure copolymers and terpolymers of low density ethylene - Google Patents

Description

The invention relates to a process for the production of high molecular weight low pressure copolymers and terpolymers of low density ethylene by co- or terpolymerization of ethylene with propylene and / or Butene-1 with the help of mixed catalysts from a titanium trichloride contact on the one hand and chlorine-containing organoaluminum compounds, on the other hand, in the liquid phase.

For different areas of application, e.g. B. the production of loom pickers and other highly stressed parts in the textile industry, in mechanical engineering and in the former. Industry, for example for screw conveyors, gears, rollers, valves and slides, you need polyethylene types with high molecular weight * settings. By the Ziegler process, high molecular weight Polyäthylentypen with RSV-values can be prepared (measured in 0,03prozentiger solution in decahydronaphthalene at 135 ⁰ C) of about 17th This corresponds to a molecular weight of about 1 million, calculated from the solution viscosity. These products have a density of 0.94.

High molecular weight polyethylene types of lower density

are not yet known after the letterpress process Polyethylene types of lower density from 0.915 to 0.935 can probably be produced. These polymers however only have molecular weights of up to approx. 50,000, calculated according to the solution viscosity

By polymerizing ethylene in butene-1 and / or CV or CVCä hydrocarbon cuts containing propylene with contacts made from halogen ortho-titanic acid esters on the one hand and those containing chlorine organometallic compounds of aluminum, on the other hand, it is not part of the prior art processes belonging to it are possible, including ethene-bututeri-1 copolymers produce low density with molecular weights up to about 500,000 (DE-OS 22 06 429).

Copolymers and terpolymers of ethylene with lower In contrast, density and extremely high molecular weight are not yet accessible.

It is the object of the present invention to provide a synthetic route which allows the advantages
the Ziegler process,
the low polymer density.
the extremely high molecular weight and
the copolymers or terpolymers
to use at the same time.

According to the invention, this object is achieved in that a solvent is used which Propylene and / or butene-1, also butane and / or propane on the one hand and butene-2 on the other hand

Surprisingly, this method makes it possible to or terpolymers with densities from 0.90 to 0.955 and Produce molecular weights up to about 5,000,000.

Suitable titanium trichloride contacts are in particular those which are obtained by reduction of Titantetrachlcrid at temperatures of 0 to - produces 10 ⁰ C and ethyl aluminum sesquichloride The preparation of such contacts is carried out by reduction of titanium tetrachloride with kohlenwasserstoffverdünntem ethylaluminum sesquichloride at 0 to - 10 ⁰ C within 4-8 Hours at a molar ratio of Ti to Al compound from 0.5 to 2.0, preferably from 1.0 to 1.5. This TiCb-containing contact can be separated from the mother liquor before use. The TiCU-containing suspension can also be used directly.

To activate this titanium trichloride contact, chlorine-containing organoaluminum compounds in a molar ratio of 04 to 5.0, preferably 1.0 to 3.0, in particular 1.5 to 23 are suitable TiCl ₃ contact ethyl aluminum sesquichloride, preferably in a 20 percent hydrocarbon solution. To the unseparated TiCl ₃ -SuS-pension, which contains ethylaluminum dichloride from the reduction, is added so much diethylaluminum monochloride that ethylaluminum sesquichloride is formed. When activated with aluminum trialkyls, aluminum dialkyl hydrides and aluminum dialkyl chlorides, mixtures of the individual homopolymers are formed in addition to the copolymers or terpolymers.

For this reason, ethylaluminum sesquichloride is preferred to activate the isolated TiCb, as described above and in a molar ratio of 0.5 to 5, preferably 1.0 to 3.0, in particular 1.5 to 2.5, how a mixed catalyst is obtained when using such an activated titanium trichloride, the Co- or terpolymers can be formed predominantly free of homopolymers.

The contacts are preferably used in a concentration of 0.1 to 10mmol / 1, with molar

ratios of Al to Ti yon 1.0 to 3.0, preferably 1.5 to RSV 2A The polymerization is carried out at temperatures from 0 to 10Q ⁰ C, preferably at temperatures from 50 to 90 ⁰ C, in particular at 60 to 80 ⁰ C, and carried out at pressures up to 50 atmospheres, in particular from 10 to 40 atmospheres

Suitable butane are n- and i-butane as well as any mixture of these substances. The butene-2 can be found in the cis or trans form and any mixtures thereof. The mixing ratio Propane / butane to butene-2 can vary within any limits. Mixing ratios propane / butane are preferred to butene-2 from 50:50 to 90:10.

Surprisingly, it has also been found that the proportion of propylene and / or 1-butene in the solvent can be present and the production of the inventive Substances allowed depends on the polymerization temperature

At a polymerization temperature of 0 to 100 ° C this proportion should not exceed 15 mol percent, namely the propylene proportion should be 5% and the butene-1 proportion Do not exceed 15%.

However, is polymerized at temperatures which are between 0 and 80,70,60 or 40 ⁰ C, the proportion may propylene 10,25,50 or 95 mole percent and the butene-1 moiety 25,60,95 or 95 mole percent.

This finding is surprising and valuable because one now has a multitude of Variation options in the hand to z. B. starting always to come to comparable polymers of different gas mixtures or to z. B. starting from the same gas mixture, modifying the polymers within even wider limits than previously was possible.

Also compared to older methods of manufacturing of ethene-butene-1 copolymers such as DE-PS J5 RSV 14 45 303 it is surprising that for the production of ethylene copolymers or tert-polymers, if necessary, only a very low butene-1 and / or propene content needed

The new process allows polyethylene co- and terpolymers with a density of about 0.90 to 0.955 and molecular weights of about 30,000 to about 5,000,000. There are thus polyethylene groups received, which so far neither according to the high pressure nor according to the low or medium pressure process " Ren could be produced.

example 1

A mixture of 0.8 part by weight of butane, 0.28 part by weight of 2-butene and 0.12 part by weight of 1-butene (10 mol percent) is placed in a 5-liter laboratory autoclave. A contact of 0.00128 parts by weight of a titanium trichloride, which by reducing 1 mol of titanium tetrachloride (100 percent) at -5 ° C with 1.4 mol of ethylaluminum sesquichloride (molecular weight 123.7; 20 percent in hexane) within 6 hours, a subsequent post-reaction time of 15 hours at 0 to 10 ⁰ C and separating the precipitate was obtained, and 0.00206 parts by weight of ethylaluminum sesquichloride is added. The temperature is increased to 80 ° C. and ethylene is injected up to a pressure of 15 atmospheres. The polymerization is carried out in a time of 4 hours at 8O ⁰ C.

The pressure is kept at 12 to 15 atmospheres by pushing in ethylene. After letting down the pressure, cooling μ and decomposition with 0.01 part by weight of methanol, 0.336 part by weight of an ethylene-butene-1 copolymer with the following property values is obtained:

30 dl / g

density (calculated according to the Yield stress Solution viscosity 5 Elongation at yield stress as polyethylene) Tear resistance 0.9220 g / cm ³ 10 elongation at break 149 kgf / cm ² Tensile impact strength 23% Softening point 333 kgf / cm ² IR analysis 410% Double bonds / 1000 C > 1500 kp cm / cm ^{2 15} trans 115-C vinyl vinyliden CH3 / IOOC <0.02 0.06 <0.02 13th

Example 2

12 parts by weight of a mixture of 70% butane, 25% butene-2 and 5% butene-1 are placed in a 50-1-50 atmospheric kettle. and 0.0103 parts by weight of ethyl aluminum sesquichloride is added. The temperature is raised to 6O ⁰ C is increased, the polymerization is within 2 hours at 6O ⁰ C and a pressure of 30 atm performed after addition of 0.1 part by weight of methanol is cooled to 20 ° C and the unreacted ethylene with butene-butane - Mixture relaxed 3.2 parts by weight of a polyethylene are obtained which has the following properties:

42 dl / g

Ä # about 4 000 000 density 03226 g / cm ³ Yield stress 154 kgf / cm ² Elongation at yield stress 23% Tear resistance 348 kptofl ² Elongation at break 452% Tensile impact strength > 1500 kp cm / cm ² IR analysis Double bonds / 1000 C trans <0.02 vinyl 0.05 vinyliden <0.02 CH _3/100 0.95

Example 3

1.8 parts by weight of a mixture of 60% butane, 20% butene-2 and 20% butene-1 are placed in a 5-liter laboratory autoclave. A contact of 0.0018 parts by weight of a titanium trichloride contact prepared as described in Example 1 and 0.0029 parts by weight of ethylaluminum sesquichloride is added. At 80 "C, ethylene is added up to a pressure of 15 atmospheres. Hydrogen is added up to a partial pressure of I atmospheres. After a polymerization time of J hours, 0.418 parts by weight of an Athens-butene-1 copolymer with a butene content of II ⁰ O is obtained .

RSV 6.44 dl / g

/ Wvelwa J5J IHM)

MF _1W2 ,, 6 0.12 g / 10 min.

MFi90rt 0.92 g / 10 mm.

Density 0.9180 g / 1111 ¹

Yield stress 78 kp / cm '

Elongation at yield stress
Tear resistance
Elongation at break
IR analysis
Double bond / 1000 C

trans-middle-class

vinyl

vinvliden

33%

101 kgf / cm ²

657%

036 0.69 0.03

When 3 atmospheres of hydrogen are added, a copolymer with an RSV value of 23 dl / g is obtained.

Example 4

According to the information in Example 3, ethylene in 1.8 parts by weight of a mixture of 60% butane, 25% Butene-2 and 15% butene-1 polymerized. 0376 parts by weight of an ethene-butene-1 copolymer are obtained with a 1-butene content of 9%.

When 3 atmospheres of hydrogen are added, a copolymer is formed with an RSV of 1.2 dl / g.

Example 7

According to the information in Example 3, ethylene is 1.8 Parts by weight of a mixture of 45% butane, 25% butene-2, 5% butene-1, 20% propane and 5% propylene polymerized. This gives 0368 parts by weight of an ethene-propene-butene-1 terpolymer with the following

Property values:

RSV

MF | 9 (W2.! ₆

density

Yield stress Elongation at yield stress Tear resistance Elongation at break

IR analysis
Double bonds / 1000 C

trans-middle-class

vinyl

vinyliden

12JS6 dl / g Ai- / about 812 000 not measurable 0.9190 ε'cm ³ 86 kp / cm * 33%

169kp / em * 573%

038 0.15 0.16

Example 5

According to the information in Example 3, ethylene in 1.8 parts by weight of a mixture of 50% butane, 40% 2-butene and 10% 1-butene polymerized in the presence of 1 atm hydrogen pressure. 0392 is obtained Parts by weight of an ethene-butene-1 copolymer with a butene-1 content of about 10% with the following Property values:

RSV 5.4 dl / g Ä7v about 284,000 density 03195 g / cm ³ Yield stress 93 kp / cm * Elongation at yield stress 33% Tear resistance 151 kg / cm * Elongation at break 587% IR analysis Double bonds / ICOO C tvans-middle class 036 vin> 5 0.21 vinyliden 0.81

Example 6

According to the information in Example 3, ethylene in 1.8 parts by weight of a mixture of 40% butane, 30% Butene-2, 25% propane and 5% propene polymerized. 0374 parts by weight of an Athens-propene copolymer are obtained with the following property values:

RSV

density
is yield stress

Elongation at yield stress Tear resistance Elongation at break

W dl / g

Wvetwa240 000

03,260 g / cm ³

146 kgf / cm ²

22%

314 kgf / cm ²

443%

Example 8

According to the data of Example 3 Ethylene is used in 1.8 parts by weight of a mixture of 95% butene-1, 3% butane and 2% butene-2 at 60 ⁰ C polymerized to give 0.412 parts by weight of ethene-butene-1-Copolymer, en with the following property values:

RSV

density

Yield stress Elongation at yield stress Tear resistance Elongation at break

15.0 dl / g

Ä7vet about 1040 000

03 160 g / cm ³

72 kgf / cm ²

33%

174 kgf / cm ²

584%

Example 9

According to the data of Example 3 Ethylene is used in 1.8 parts by weight of a mixture of 7b% propene, 19% butene-1, 3% butane and 2% butene-2 at 25 ⁰ C polymerized obtained 0.143 weight parts of an ethene-propene-butene -1 terpolymers with the following properties:

RSV example 20.0 dl / g AiV about 1,530,000 density 0305 g / cm ³ Ether-soluble part 27.8% Yield stress 48 kgf / cm ² Elongation at yield stress 33% '' Tear resistance 92 kgf / cm ² Elongation at break 350% 10

According to the data of Example 3 Ethylene is polymerized in-butene 1.60 1.8 parts by weight of a mixture of 20%% butane and 20% butene-2 at 70 ⁰ C. This 0325 parts by weight of a receive ethene-butene-1 copolymer with the following Property values:

RSV 7.8 dl / g RSV 173 dl / g Mv about 447 000 Ä / v about 1250000 density 0.9310 g / cm ³ density 0.9235 g / cm ³ Yield stress 162 kgf / cm ² · '"' Stretch stress"; 107 kgf / cm ² Elongation at corner stress 21% Elongation at yield stress 50% Tear resistance 316 kgf / cm ² Tear resistance 238 kgf / cm ² Elongation at break 426% Elongation at break 493%

IR analysis 0.20 Double bond / 1000 C 0.11 trans-middle countries 0.14 vinyl Il vinyliden CHi / 100C

Claims (6)

Patent claims: 1. Process for the production of high molecular weight low pressure copolymers and terpolymers of ethylene low density by co- or terpolymerization of ethylene with propylene and / or butene-1 with The help of mixed catalysts consisting of a titanium halide contact on the one hand and chlorine-containing organoaluminum Compounds on the other hand in the liquid phase using a solvent, which contains propylene and / or butene-1, also butane and / or propane, characterized in that that a titanium trichloride known per se and as a solvent are used as the titanium halide one used which contains butene-2 2. The method according to claim 1, characterized in that the ^{polymerization is carried out at 0 to 10O 5} C and a solvent is used, the proportion of propylene of which is up to 5 mol percent or of butene-1 is up to 15 mol percent 3. The method according to claim 1, characterized in that the ^{polymerization is carried out at 0 to 80 0} C and a solvent is used, the proportion of propylene of which is up to 10 mol percent or of butene-1 is up to 25 mol percent 4. The method according to claim 1, characterized in that polymerization is carried out at 0 to 70 ° C and a solvent uses its propylene content up to 25% by mole or butene-1 is up to 60 mole percent 5. The method according to claim 1, characterized in that the ^{polymerization is carried out at 0 to 60 0} C and a solvent is used, the proportion of propylene of which is up to 50 mol percent or of butene-1 is up to 95 mol percent. 6. The method according to claim 1, characterized in that polymerization and from 0 to 4O ⁰ C a solvent is used its content of propylene and / or butene-1 up to 95 mole percent. ίο