CS199508B2 - Process for preparing copolymers of ethylene with one or more polyene hydrocarbons - Google Patents

Abstract

For the preparation of interpolymers of ethylene with one or more polyene hydrocarbons, in which at least one unsaturation belongs to a polycyclic system, the reaction is carried out in the presence of a diluent and of a special catalytic system. The latter is prepared from 1 - one or more vanadium compounds of a valency greater than two, soluble in the reaction medium, 2 - one or more aluminium compounds of the general formula R2AlX in which R is an alkyl, cycloalkyl, alkylaryl or aryl radical having 1 to 12 carbon atoms and X is chlorine or bromine, and 3 - one or more of the following compounds: organic compounds containing the grouping -CCl3, hexachlorocyclopentadiene or thionyl chloride. The polymerisation yields relative to the vanadium compound are between 30,000 and more than 1,000,000 grams of copolymer per gram of vanadium, and the polymerisation product does not require a washing stage for removal of catalytic residues, but can be recovered from the reaction slurry by centrifuging or stripping. The unsaturated interpolymers thus obtained have a random distribution of the monomer units, a high mean molecular weight, a high crystallinity of the polyethylene type and a melting point above 120 DEG C.

Description

The invention relates to a process for the preparation of copolymers of ethylene with one or more polyene hydrocarbons having at least one unsaturated bond belonging to the polycyclic system. In this process, a catalyst system based on vanadium compounds has been found which exhibits a high specific activity in the polymerization of ethylene with at least one polyene containing at least one unsaturated bond, the unsaturated bond being related to the polycyclic system.

It has now surprisingly been found that copolymers of ethylene with at least one polyene of the above type can be prepared at extremely high polymerization yields when the process is carried out. independently in the presence of either an aromatic or aliphatic solvent using the catalyst system of the invention.

The process of preparing copolymers of ethylene with one or more polyene hydrocarbons having at least one unsaturated bond belonging to the polycyclic system according to the invention is characterized in that the reaction is carried out in the presence of a solvent selected from the group consisting of aliphatic and aromatic hydrocarbons at in the presence of from 0 to 120 ° C, and in the presence of a catalyst system consisting of the reaction product of one or more of the bath compounds. where the valency of vanadium is greater than. two that are soluble in the reaction medium, one or more aluminum general compounds. formulas:

RJAlX in which it means

R is an alkyl cycloalkyl, alkylaryl or aryl radical of 1 to 12 carbon atoms, and # X is chloro or bromo,.

and one or more compounds selected from the group consisting of: --C13 organic compounds, hexachlorocyclopentadiene, and thionyl chloride.

The molar ratio of the aluminum compound (s) to the vanadium compound is generally high since the vanadium compound is used in said catalytic. system in very small quantities. In a preferred embodiment of the process of the invention. the ratio is greater than 10 and typically ranges from 50 to 500.

The molar ratio of one or more compounds selected from the group consisting of organic compounds containing a group - CCl3, hexa199508 chlorocyclopentadiene and thionyl chloride, k. one or more aluminum compounds of the general formula

RaAlX in which it means

R is an alkyl, cycloalkyl, alkylaryl or aryl radical of 1 to 12 carbon atoms, and

X is chlorine or bromine, and can be varied within a very wide range in the catalyst system, preferably from 1:20 to 1: 1.

In a preferred embodiment, the above reaction can be carried out at temperatures ranging from 20 to 80 ° C.

The process according to the invention yields polymers having a high molecular weight, a statistical distribution of monomer units, the presence of unsaturated bonds in groups outside the main chain, a high melting point and a high degree of crystallinity.

The copolymers of the invention can be readily vulcanized using conventional sulfur-based compositions to give crosslinked products similar to high density polyethylenes but better in terms of mechanical, thermal and chemical properties than the prior art copolymers.

One feature of the process for the preparation of the copolymers of the invention is that copolymers having the above-mentioned properties are obtained, wherein the residual vanadium content is obtained. The catalyst which is derived from the decomposition of the catalyst is very low even when purification of the copolymer obtained is not used. ,.

This implies a substantial simplification of the process to the extent that it is possible to remove the polymer directly from the reaction vessel and to dry it. the final wash step can be omitted completely.

For example. the compounds used for the preparation of the catalyst compositions of the present invention include: halogen halides such as vanadium chloride and vanadyl chloride, alcoholates such as vanadyl triisopropylate, chelates such as for example vanadium triacetylacetonate and vanadyl diacetylacetonate, and all complex compounds. As the second component of the catalyst system of the present invention, aluminum dihydrocarbyl halides are exemplified, such as diethyl aluminum monochloride, diisobutyl aluminum monochloride, and diethylaluminum monobromide.

As mentioned above, the third component of the catalyst system of the present invention is hexachloropentadiene or thionyl chloride or such. organic compounds which contain at least one group - CCl 3 in their molecule, such as. trichloroacetic acid and. her . esters, trichlorotoluene and the like.

According to a preferred embodiment of the process of the invention, the polymerization reaction is carried out in the presence of monomers to be polymerized or at least in the presence of one. and in the presence of a solvent, which solvent may be either an aliphatic or aromatic hydrocarbon.

The choice of one or the other of the above solvent types is determined by the requirement. to the molecular weight of the desired resulting polymer, it being noted that aliphatic solvents contribute to the highest molecular weight, and further. Yippee . the choice of the above solvent dictated. availability, costs, and other factors.

It is also preferred to use mixtures. both types of the above hydrocarbons as solvents.

Polymerization temperature. moves as. already mentioned, ranging from. 0 ° C to 120 ° C, with a. successful use of temperatures in the range. from 20 to 80 ° C, which. means the range in which the highest catalytic effect of the system according to the invention occurs, wherein, when using temperatures in the above range, a cooling cycle is not required to dissipate the heat of reaction.

The polymerization yields range from 30,000 to more than 1,000,000 grams of copolymer per gram of elemental vanadium used in the catalyst composition.

Number of monomers fed. into the reaction at the above. conditions. it is at least two: one of the monomers is ethylene and the other or others. is one or. more compounds containing at least two unsaturated bonds, one of which is unsaturated on the polycyclic ring of bicyclic (2,2,1) -2-heptene. Monomers from this second group react during polymerization to cleave the fused cyclopentene ring, leaving the remaining unsaturated bond intact. polymer chain.

Examples of such monomers include:

5-ethylidene-bicyclo- (2,2,1) -2heptene (ethylidennorbornene),

8-Isopropylpyrrolidin-10-yl (2,2,2,1 J -2,6-diene (isopropylidenedicyclopentadiene)),

5- (2 ', 4'-dimethyl-penta-1', 3'-dienyl) bicyclo- (2,2,1'-2-heptene (-dimethylpentadienylnorbornene) and its isomers, [bicyclo- (2,2'-dimethyl-pentadienylnorbornene)] 1) -3'-heptenyl] -3 ', 9', 5'-trimethylcyclohexa-1,3-dienylmethane [norbornenyltrimethylcyclohexadienylmethane] and its isomers and other substances.

The copolymerization of ethylene with one or more cyclic hydrocarbons of the above type, which is catalyzed by the above catalyst mixture and carried out under the conditions of the invention, provides novel hydrocarbon polymers having properties of considerable practical importance.

In particular, copolymers having 99.9% to 95% ethylene units and 0.1 to 5% polyene units of the above type have some physical properties, such as melting point and specific gravity, which only they differ little from high density polyethylenes, which 'have' the same average molecular weight.

On the other hand, the presence of unsaturated bonds in the side chain and their statistical distribution both within the individual macromolecules and between the chains makes it possible to obtain crosslinked products having physicochemical thermal and chemical properties undoubtedly better than. the best types of polyethylenes. The copolymers of the present invention are highly reactive under vulcanization conditions and are well known to those skilled in the art. those skilled in the art using sulfur and accelerators as crosslinkers. . For example, it may be noted that. a very low content of ethylidene norbornene (in the range of 0.2 to 0.5 mol%) in the ethylene copolymer is sufficient to obtain vulcanizates with more than 80% gel. When ethylidene norbornene is present in an amount ranging from 0.5 to 1 mole percent, a 100% gel can be obtained.

As a result of the above process, a product having a suitable comonomer units statistical distribution index was obtained which could not be achieved by the previously used processes using other ethylene comonomers not used in the present invention.

In the particular case of copolymerization of isopropylidenedicyclopentadiene with ethylene, it is possible directly to obtain a polymerization product having a structural branching which causes high viscosity of the molten mass. However, this product is easily ground in an open mill and is capable of expanding in a press even though no curing agents are added.

The copolymers of the invention are not only suitable for the preparation of lightweight materials, but can be used in all cases where the highest possible impact resistance and stress corrosion resistance are required together with high mechanical strength and thermal resistance, as well as resistance to chemical agents. ·

The following are practical examples of the process of the invention which:. they illustrate details of embodiments of the process without limiting the spirit of the invention.

He did

In this example, a 22-liter steel autoclave is filled which. it is equipped with a mechanical stirrer and thermostatically controlled to 60 ° C, with the following reactants in the following order:

toluene 16 liters

Ethyl AlCl 100 millimoles (= 13.4 g) ethylidennorbornene 12.5 grams

At this internal temperature above, ethylene is fed into the autoclave until the pressure reaches 50 psi and subsequently hydrogen is introduced into the autoclave until the total pressure is 50 psi.

In a further procedure, two solutions prepared from the following components are fed in parallel to the autoclave by means of two piston pumps over a period of approximately 40 minutes:

1) · ...

toluene. 200 milliliters vanadium triacetylacetonate 0.02 millimoles (6.96 milligrams) CCI3COOC2H5 6 millimoles

2) toluene 100 ml of ethylidennorbornene 100 grams

The polymerization reaction was stopped by the action of methanol (200 millimoles) after 45 minutes from the start of the reaction when the vanadium catalyst was added to the reaction mixture, during which time the total pressure was maintained at 0.55 MPa by supplying ethylene. that was used above. The polymer slurry thus obtained is centrifuged in a cuvette centrifuge and the solid is dried at 50 ° C and vacuum.

The dried polymer exhibits the following properties:

ethylidennorbornene units of MF12, 16 flow index.

MFia e melting point (DSC)

Example 2

1.3 mol%

4.48 g / 10 min

114.4 g / 10 min

125 ° C

According to this example, the 5 liter stainless steel autoclave, equipped with a mechanical stirrer and thermostatic means to maintain it at 60 ° C, is filled with a vacuum solution with the following composition:

toluene 1300 ml

EtzAlCl 11.7 millimoles

Ethylene is then added to the vessel by successive addition until the equilibrium pressure reaches 0.45 MPa and hydrogen is added until the total pressure reaches 0.5 MPa. Using two piston pumps, two solutions having the following composition are then fed in parallel and successively over a period of 30 minutes:

1) toluene 100 millimoles vanadium triacetylacetonate 0.019 millimoles CCI3COOC2H5 5.85 millimoles

2) toluene 100 ml ethylidennorbornene 15 grams

In addition, ethylene is added to the autoclave until equilibrium pressure is reached at 50 psi and then hydrogen until the total pressure reaches 50 psi. Thereafter, two solutions are fed in parallel and successively, over a period of 30 minutes, with two solutions, which are prepared as follows:

1) toluene 100 milliliters vanadium triacetylacetonate 0.019 millimoles CCl3COOC2H5 5.85 millimoles

2) toluene 100 ml ethylidennorbornene 15 grams

During the process of this example, the temperature inside the autoclave is maintained at 60 ° C and the total pressure in the autoclave is maintained at 0.5 MPa, which pressure is maintained by feeding the reacted ethylene. 40 minutes after the two pumps were started, methanol (50 ml) was introduced into the autoclave to terminate the catalytic activity and the polymer thus prepared was washed and dried under vacuum at 50 ° C.

The above procedure yields 140 grams of dry product having the following characteristics:

load index 2.12 kg (ΜΠζ, ιβ, ASTM D-1236-65 T) 0.47 g / 10 min load index 21.6 kg (MFI21.8) melting point (differential thermal analysis) [η ] (in decalin at 135 ° C) copolymerized ethylidennorbornene (IR analysis)

16.9 g / 10 min

120 [deg.] C

1.79 dl / g

4.8 wt.

The polymer thus obtained is combined with the following components (parts per 100 parts of polymer):

zinc oxide 5 parts stearic acid1

2,2‘-dimethyl-bls- (4-methyl-tert-butylphenol)

N-oxydiethylbenzthlazole-2-sulfenamide1,5 dibenzthlazolyldisulfide0,5 sulfur3

The polymer compounded with the above ingredients is cured under pressure at 180 ° C for 30 minutes. Following the procedure of this example, a completely gelled product (100% insolubility in boiling xylene) was obtained, having an impact strength of 71.90 kj / m ² .

Example 3

In this example, the same procedure and autoclave as in Example 1 were used. In contrast to this example, the following batch was used:

n-hexane Et2AlCl ethylidennorbornene

1300 milliliters

11.7 millimoles gram

The temperature in the autoclave was maintained at 60 ^Q C and the pressure was maintained at 0.5 MPa, based on ethylene, and 0.1 MPa, relative to hydrogen. The autoclave is then fed successively with solutions having the following composition, the addition being carried out over a period of 20 minutes:

1) vanadium n-hexane triacetylacetonate CCl 3 COOC 2 H 5

100 milliliters

0.013 millimoles

5.85 millimoles'

2) n-hexane 100 moles of ethylidennorbornene 9 grams

The procedure was carried out at 60 ° C and 0.6 MPa for 30 minutes. 135 grams of dry polymer are obtained having the following properties:

MFI2.16

MFI21.6 ethylidennorbornene [η] (in decalin at 135 ° C)

1.38 g / 10 min

60.4 g / 10 min

1.1% w / w

1.38 dl / g

The above product is then combined with sulfur and accelerators as described in Example 1 to form. product content. 87% gel and an impact strength of 61.51 < 3 > kj / m &^lt; ^{2 &gt};.

Example 4

The procedure of this example was carried out in the same autoclave as described in Example 1, to which the following mixture was sucked:

toluene

Ethyl AlCl · norbornenyltrimethylcyclohexadlenylmethane

1300 milliliters

11.7 milimo, lů gram

The temperature in the autoclave was maintained at 80 ° C by thermostatization, and then ethylene was fed until the pressure rose to 50 psi, and hydrogen was then added until the temperature was reached. pressure 0.4 MPa. The polymerization starts after the solution of the following composition is introduced into the autoclave:

Toluene 1 C 2 O 0 milliliters vanadium triacetylacetonate 0.013 millimoles

CCl 3 COOC 2 H 5 5.85 millimoles

This solution was added at 25 minute intervals.

At the same time, a toluene solution (100 ml) containing dissolved solution was fed into the autoclave. 9 grams of norbornenyltrimethylcyclohexydienylmethane. After the polymerization was carried out for 30 minutes, 175 grams were obtained. dry polymer (264,000 grams of polymer per gram of elemental vanadium contained in the catalyst) having the following characteristics:

[η] (in decalin at 135 ° C) 1.52 dl / g

MFI2.16 0.281 g / 10'min

MF121.6 23.5 g110 min melting point 129 ⁰ C (DSC)

The polymer thus obtained can be crosslinked using sulfur and accelerators. combining the blends of which the example is given in Example 1 to give a product with a gel content of 60.9% and an impact strength of 32.37 kj / m 2.

Example 5

The procedure of this example is the same as that of Example 3, except that this example is used. replace toluene with an equivalent volume of normal hexane.

At 35 minutes of polymerization, 120 grams of polymer product is obtained having the following properties:

[η) (in decalin at ^135-C) of 1.06 dl / g

MFI2.16 2.78 g / 10 mm

MFI21.6 14Ю.2 Gho min · melting point (DSC) 127 ° ^C

The product thus prepared is then combined. with sulfur and accelerators and cured as described in Example 1 to give a product containing 58.5% gel.

Example 6

According to this. In the example, copolymerization of ethylene with dimethylpentadienylnorbornene is carried out in the same apparatus as used in the procedure of Example 1. The solution to be introduced into the autoclave by suction has the following composition: toluene 1300 milliliters

EtzAlCl. 11.7 millimoles of dimethylpentadienyl- 1 gram of norbornene

In a further process, ethylene is fed to the autoclave at 80 ° C. the pressure does not rise to · 0.35. And then hydrogen is introduced until the total pressure reaches 0.4 MPa.

During the procedure of this

For example, a solution containing: toluene vanadium triacetylacetonate CCI3COOC2H5 ‘ 100 milliliters 0.017 millimoles 5.85 millimoles and a second solution comprising: toluene. dimethylpentadienylnórbornen 100 milliliters 9 grams

30 minutes from the start of the reaction, the polymer is removed. from an autoclave, wherein. his. the weight after drying is. 125 grams. Product analysis showed the following features:

[η] (in decalin at 135 ° C) 1.74 dl / g

MFI2.16 '. 0.079 g / 10 min

MFI 21.6 10.68 g / 10 min, melting point (DSC) 129 ° C.

The polymer was crosslinked with sulfur (see Example 1) with a gel content of 60.8%.

Example 7

In this example, a 2 liter stainless steel autoclave equipped with an autoclave was used. mechanical stirrer

199568 no

and a thermostatic sheath which is evacuated and then filled with suction with the following composition of composition:

n-hexane 900 millimoles

Ethyl AlCl 9 millimoles isopropylidenedicyclopentadiene 2 milliliters

Ethylene was then fed to the autoclave at 90 ° C until the pressure reached 0.6 MPa and then hydrogen until the total pressure reached 0.8 MPa. Then, a solution of the following composition is rapidly introduced into the above mixture in an autoclave: n-hexane 210 ml vanadium triacetylacetonate (saturated solution in toluene) 0.05 millimoles

Next, using the same piston pumps as used above, another solution of the following composition is introduced gradually (over a period of 40 minutes) immediately after the above addition:

n-hexane 80 ml

CGI3GOOCH3 4.5 millimoles isopropylidenedicyclopentadiene 4 milliliters

The procedure was carried out at 90 ° C and 0.8 MPa (this pressure was kept constant by the addition of additional ethylene) and the process was terminated 60 minutes after the addition of the vanadium compounds. The polymer thus obtained is separated on the filter from the other slurry and further dried under vacuum at 50 ° C. 63 g of dry product are obtained. Analysis of the final product showed the following results:

[η] (in decalin at 135 ° C) 1.25 dl / g MFI ₂ , i6 0.08 g / 10 min MFI21.6 18.4 g / 10 min melting point (DSC) 122 [deg.] C gel content (insoluble 40% in boiling xylene)

The polymer obtained is melt-cured at 180 ° C for 30 minutes, before being cured with the following mixture, the composition of which is expressed in terms of 100 parts by weight of polymer:

zinc oxide5 stearic acid1

2,2‘-Dimethyl-bis- (4-methyl-t-butyl-phenol) 1

N-oxydiethylbenzthiazole-2-sulfenamide1,5 dibenzthiazyldlsulfide0,5 sulfur3

In the gel thus obtained, the gel content was 71.3 percent.

Example

A toluene solution (900 ml) containing Et2AlCl (9 ml) and isopropylidenedicyclopentadiene (1 ml) is initially introduced into the autoclave into the same apparatus and the same procedure as described in Example 7. followed by ethylene and hydrogen until the pressure reached an equilibrium value at 80 DEG C. of 0.5 MPa and a total value of 0.8 MPa, and finally vanadium triacetylacetonate (0.05 mmol) dissolved in toluene was added to the reaction mixture. (20 ml).

The polymerization proceeds actively for a further 48 minutes, during which a mixture of CCl3COOCH3 (4.5 millimoles) and isopropylidenedicyclopentadiene (5 milliliters) is added to the autoclave mixture, which is diluted with 80 milliliters of toluene. After addition of the vanadium compound, after 60 minutes the polymer slurry from the autoclave is separated off on a filter and the solid polymer is dried, yielding 58 grams of product.

The properties of the obtained product are as follows:

[η] (in decalin at 135 ° C) 1.47 dl / g

MFI2.16 0.0415 g / 10 min

MFI21.6 16.86 g / 10 min melting point (DSC) 126 ° C gel content 37%

The polymer thus obtained is easily processed in an open mill. When the product is subjected to heat treatment in the presence of the components of Example 1, the gel content is increased to 75%.

SUBJECT

Claims (7)

SUBJECT A process for the preparation of copolymers of ethylene with one or more polyene hydrocarbons having at least one unsaturated bond belonging to a polycyclic system, characterized in that the reaction is carried out at a temperature ranging from - 0 to 120 ° C in the presence of a solvent selected from -aliphatic and aromatic groups. hydrocarbons and a catalytic system consisting of the reaction product of one or more vanadium compounds, wherein the valency of the vanadium is greater than - two, which are soluble in the reaction medium, of one or more aluminum compounds of the general formula R2AIX in which-means R is an alkyl, cycloalkyl, -alkylaryl or aryl radical containing from 1 to 12 carbon atoms, and X is chlorine or bromine, and from one or more compounds selected from the group consisting of organic compounds containing a group - CC 13, hexachlorocyclopentadiene and thionyl chloride. 2. The process of claim 1, wherein a catalyst system having a molar ratio of the aluminum compound (s) to the vanadium compound (s) greater than 1µ is used. vynalezu 3. Method according to points. 1 and 2, characterized in that a catalytic system with a molar ratio of aluminum compound (s) to vanadium compound (s) in the range of 50 to 500 is used. 4. Way - by - points. 1 to 3, characterized in that a catalyst system with a molar ratio of one or more compounds selected from the group consisting of organic compounds containing a group is used. - CC13, hexachlorocyclopentadiene and thionyl chloride, - to - one or more aluminum compounds of the general formula, R2AIX in which is R is an alkyl, cycloalkyl, alkylaryl or -aryl radical containing from 1 to 12 carbon atoms, and X is chlorine or bromine, ranging from 1:20 to 1: 1. 5. A process according to any one of claims 1 to 4, wherein said reaction is preferably carried out at a temperature in the range of from -20 to 80 degrees Celsius. 6. The process of claims 1 to 5, wherein the polymerization product is separated from the reaction slurry by centrifugation or evaporation of the volatile components. Severograna, n. Race 7, Most