JPH05112607A - Production of chlorinated polyolefin - Google Patents

Abstract

PURPOSE:To obtain the subject polymer good in stability to coloring and scorching without adversely affecting the ozonosphere by using trichloroethane as a solvent in chlorinating a polyolefin in the solvent. CONSTITUTION:A polyolefin is dissolved or suspended in a solvent composed of 1,1,2-trichloroethane, reacted and chlorinated with chlorine gas or sulfuryl chloride in the presence of a catalyst composed of a radical former (preferably alpha, alpha-azobisisobutyronitrile). The reactional temperature is preferably 60-130 deg.C and the reactional pressure is preferably 0-7kg/cm<2>. Furthermore, the 1,1,2- trichloroethane is successively stirred and washed with an aqueous solution of sulfuric acid and an aqueous solution of hydrochloric acid, then stirred and washed with distilled water until the organic layer becomes neutral. Thereby, alcoholic compounds and epoxy compounds contained in the 1,1,2-trichloroethane are preferably removed and used for the reaction.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a method for producing a chlorinated polyolefin. More specifically, it relates to a production method for producing a chlorinated polyolefin by dissolving or suspending a polyolefin in 1,1,2-trichloroethane and carrying out a chlorination reaction.

[0002]

It is known to dissolve or suspend a polyolefin in a solvent to produce a chlorinated polyolefin. Carbon tetrachloride has also been used as the solvent. However, as a result of the revision of the “Montreal Protocol on Substances that Deplete the Ozone Layer” (hereinafter referred to as the “Protocol”) conducted in June 1990, carbon tetrachloride became a regulated substance, and as a result, chlorine from 1995 onwards became The use of carbon tetrachloride for the commercial production of modified polyolefins has been difficult. Therefore, a new chlorinated polyolefin production method that does not use carbon tetrachloride has been desired.

[0003]

The present invention, from the viewpoint of global environmental protection, is a substance that is not subject to the regulation of the Protocol 1,1,
An object of the present invention is to provide a method for producing a chlorinated polyolefin having commercial value by using 2-trichloroethane as a solvent.

[0004]

That is, according to the present invention, when a polyolefin dissolved or suspended in a solvent is used as a solvent in a chlorination reaction using chlorine gas or sulfuryl chloride with a radical generator as a catalyst, A method for producing a chlorinated polyolefin characterized in that 1,2,2-trichloroethane is used as a solvent. The details will be described below.

[0005]

The solvent used in the present invention is 1,1,2-trichloroethane, which is a non-regulated substance in the Protocol.

The reaction for chlorination uses chlorine gas or sulfuryl chloride as a catalyst with a radical generator as a catalyst.
React with a polyolefin dissolved or suspended in 1,2-trichloroethane. The reaction temperature is 40 to 150 ° C,
The temperature is preferably 60 to 130 ° C., and the reaction pressure is 0 to 10
kg / cm ^2, preferably 0~7kg / cm ^2.

As the radical generator, an azo compound or an organic peroxide is used. Examples of the azo compound include α, α′-azobisisobutyronitylyl, azobiscyclohexanecarbonitrile, and 2,2′-azobis (2,4-dimethylvaleronitrile). Examples of the organic peroxide include Examples thereof include benzoyl peroxide, acetyl peroxide, t-butyl peroxide, t-butyl perbenzoate and the like. An azo compound is preferable, and α, α′-azobisisobutyronitryl is particularly preferable.

Examples of the raw material polyolefin include high-density polyethylene (HDPE), low-density polyethylene (LDPE), and linear low-density polyethylene (LLDP).
E), ethylene homopolymers and copolymers such as ultra low density polyethylene (VLDPE), ethylene / vinyl acetate copolymer (EVA) and ethylene / propylene copolymer (EPM).

As a method for separating the product polymer from the solvent after completion of the reaction, steam distillation, a drum dryer, and an extruder with a vent are known, and these methods are used to separate the two.

However, in the recovered 1,1,2-trichloroethane, a part of 1,1,2-trichloroethane is chlorinated during the reaction and is by-produced, 1,1,2,2-.
Contains tetrachloroethane. By using this again in the reaction, the concentration of 1,1,2,2-tetrachloroethane in the recovered 1,1,2-trichloroethane is gradually increased. Since this 1,1,2,2-tetrachloroethane has a high boiling point of 146.3 ° C., 1,1,2,2 is contained in the chlorinated polyolefin obtained by being separated from the solvent.
-Tetrachloroethane remains and has various adverse effects on the physical properties of the elastomer. Therefore, the collected 1,1,2
-It is important to remove 1,1,2,2-tetrachloroethane from trichloroethane and suppress the by-product of 1,1,2,2-tetrachloroethane itself.

The method for removing 1,1,2,2-tetrachloroethane from the recovered 1,1,2-trichloroethane is conveniently by distillation. The 1,1,2-trichloroethane thus purified is recycled to the reactor.

On the other hand, as a method for suppressing the production of 1,1,2,2-tetrachloroethane during the reaction, first, the process of avoiding the use of chlorine as a chlorinating agent and using sulfuryl chloride alone is effective. In particular, the reaction temperature at this time is preferably relatively low at 60 to 130 ° C.

It is also important to remove the alcohol compound and / or the epoxy compound from the 1,1,2-trichloroethane solvent used in the present invention to carry out the reaction.

Commercially available 1,1,2-trichloroethane often contains 0.5 to 2.0% of alcohol compounds and / or epoxy compounds as impurities.
The alcohol compound mentioned above is a compound having a hydroxyl group, and examples thereof include ethyl alcohol and butyl alcohol. Further, the epoxy compound so far referred to is a compound having an epoxy group, for example, 1,2-
Examples thereof include epoxy propane and 1,2-epoxy butane.

The chlorinated polyolefin synthesized by using 1,1,2-trichloroethane containing an alcohol compound and / or an epoxy compound as an impurity as a solvent is colored in pale yellow, and the compound is liable to cause scorch. For example, chlorinated polyolefin has excellent properties such as flame resistance, weather resistance, ozone resistance, chemical resistance, and electrical characteristics, so that it is a resin modifier such as vinyl chloride, a light-colored electric wire, a light-colored sponge. Used for. Since these are characterized by their beautiful color, coloring of the chlorinated polyolefin itself is not preferable. Further, the short scorch time of the compound and the tendency to cause scorch are a problem because the processing safety is impaired when the chlorinated polyolefin is processed into final products such as hoses and electric wires.

As a result of intensive studies by the present inventors, the chlorinated polyolefin synthesized using 1,1,2-trichloroethane from which the alcohol compound and / or the epoxy compound has been removed as a solvent is pure white and shows no coloration. It has also been found that the chlorinated polyolefin has excellent scorch stability and is commercially valuable. It was also found that there is no difference between the two in terms of strength, elongation, hardness, etc. after vulcanization, and there is no characteristic that distinguishes them from the viewpoint of vulcanization physical properties. However, the fact that there is no difference in the vulcanized physical properties does not detract from the significance of the present invention.

In the present invention, a method for removing an alcohol compound and / or an epoxy compound from a 1,1,2-trichloroethane solvent includes, for example, a 1,1,2-containing alcohol compound and / or epoxy compound as impurities. There is a method of removing trichloroethane by stirring and washing with an aqueous solution of sulfuric acid, then washing with stirring with an aqueous solution of hydrochloric acid, and further by washing with distilled water until the organic layer becomes neutral.
This washing method is simple and industrially preferable.

The chlorinated polyolefin referred to in the present invention includes, for example, chlorinated polyethylene, chlorinated ethylene / propylene copolymer, chlorinated ethylene / butene copolymer, and chlorinated ethylene. Examples include hexene copolymers and chlorinated ethylene / vinyl acetate copolymers.

The obtained product is compounded and kneaded in the same manner as a conventional rubber or resin to be used as a vulcanized product or an unvulcanized product. Compounding agents include vulcanizing agents such as magnesia and calcium hydroxide, reinforcing agents such as carbon black and white carbon, fillers such as calcium carbonate and talc,
Examples thereof include compounding agents for rubber or resin such as plasticizers, processing aids, antioxidants and vulcanization accelerators. Examples of the vulcanizing method include general methods such as steam vulcanization, UHF vulcanization, hot air vulcanization, injection, mold and rotocure.

For the end use, like the existing chlorinated polyolefin, wire coating material, PVC, PE, PP, PS and A
Resin modification such as BS, rubber magnets, light electric parts, automobile parts,
Examples include rubber parts, waterproof sheets and sponges.

[0021]

The present invention will be described in more detail based on the following examples, but these are examples for assisting the present invention and the present invention is not limited to these examples. The values used in these examples were obtained according to the following measuring methods. Chlorine content: Combustion flask method Physical properties of unvulcanized rubber: JIS K 6300 Physical properties of vulcanized rubber: JIS K 6301 Product hue: Visually Stabilization of product hue due to accelerated deterioration: 70 ° C. Gear oven method, visual 1 Content of 1,1,2,2-tetrachloroethane in 1,1,2-trichloroethane: Gas Chromatography Example 1 1-Butanol and 1,2-butanol contained in 1,1,2-trichloroethane by the following method prior to reaction The 1,2-epoxybutane was removed. 5 kg of Kanto Chemical Co., Ltd. 1,1,2-trichloroethane and 2.5 kg of 26% sulfuric acid aqueous solution
And were put into a 10 liter flask with a lower mouth and vigorously stirred, and after standing, the lower organic layer was extracted, and then the extracted organic layer and 5 kg of 36% hydrochloric acid aqueous solution were put into a 10 liter flask with a lower mouth and vigorously stirred. After standing still, the lower organic layer is extracted. Then, the extracted organic layer and 5 kg of distilled water were placed in a 10-liter flask with a lower opening and vigorously stirred, and after leaving still, the operation of extracting the lower organic layer was repeated 3 times to obtain impurities 1-butanol and 1, The 2-epoxybutane was removed. Molecular sieves 4A in the extracted organic layer
Of 150 g was added and the mixture was dehydrated by stirring with a stirrer.

A 30-liter glass-lined autoclave was charged with 1-butanol and 1,2 by the above procedure.
28 kg of 1,1,2-trichloroethane from which the epoxy butane has been removed and a melt index of 3.8 g / 10
Min., 1.96 kg of high-density polyethylene having a density of 0.963 g / cc was charged. Polyethylene was uniformly dissolved by passing steam through the jacket of the reactor and holding it at 120 ° C. for 2 hours. Also, during this period, nitrogen gas was introduced into the reactor at a flow rate of 15 liters / minute to eliminate air mixed in the reactor. 2.65 g α as a radical initiator,
α'-Azobisisobutyronitryl was dissolved in 2.9 kg of 1,1,2-trichloroethane from which 1-butanol and 1,2-epoxybutane were removed. While continuously adding this solution to the reactor, chlorine gas was introduced into the reactor from another charging port at a flow rate of 6 liters / minute for 130 minutes to carry out the reaction. The reaction temperature was kept at 115 ° C. and the reactor pressure was kept at 3.5 kg / cm ² . After the reaction was completed, the pressure was returned to normal pressure and the reactor temperature was lowered to 70 ° C.
Nitrogen was introduced while keeping the temperature at 0 ° C. to remove chlorine gas and hydrogen chloride gas remaining in the reaction solution. 43 g of 2, as a stabilizer
After adding 2'-bis (4-glycidyloxyphenyl) propane, this solution was fed to a drum dryer heated to 155 ° C to separate the product chlorinated polyethylene from the solvent.

The product had a pure white hue and analysis showed that the chlorinated polyethylene contained 35.5% chlorine. Mooney viscosity of raw rubber (ML1 + 4,10
(0 ° C.) was 62. The hue stability of the product was tested by an accelerated test by heat, but no change in hue was observed even after 10 days at 70 ° C.

Further, the product was kneaded according to the composition shown in Table 1, and the physical properties of an unvulcanized product represented by scorch time and the vulcanized physical properties such as tensile strength were measured.

Table 1 ──────────────────────── Parts by weight Chlorinated polyethylene 100 Magnesia 10 SRF * 1) 30 DOS * 2) 10 TAIC * 3 ) 4 DCP * 4) 3 ──────────────────────── * 1) Carbon black * 2) Di- (2-ethylhexyl) sebacate * 3) Triallyl isocyanurate * 4) Dicumyl peroxide The obtained values are summarized in Table 2.

On the other hand, 1, separated by a drum dryer
As a result of analysis, 0.3% of 1,2-trichloroethane was chlorinated and produced 1,1,2,2-tetrachloroethane. This 1,1,2-trichloroethane is distilled to remove 1,1,2,2-tetrachloroethane,
Used for the next reaction.

Example 2 Polyolefin as a raw material had a melt index of 1.1 g /
Min, a high density polyethylene having a density of 0.965 g / cc was used, and the reaction was carried out in the same manner as in Example 1 except that chlorine gas was introduced at a flow rate of 6 liters / minute for 150 minutes, and then the product was separated. .

The product had a pure white hue and analysis showed that the chlorinated polyethylene contained 37.5% chlorine. Mooney viscosity of raw rubber (ML1 + 4,1
(00 ° C) was 106. The hue stability of the product was tested by an accelerated test by heat, but no change in hue was observed even after 10 days at 70 ° C.

Further, the product was kneaded according to the composition shown in Table 1, and the physical properties and vulcanized physical properties of the unvulcanized product were measured. This is summarized in Table 2.

On the other hand, 1, separated by a drum dryer
As a result of analysis, 0.3% of 1,2-trichloroethane was chlorinated and produced 1,1,2,2-tetrachloroethane. This 1,1,2-trichloroethane is distilled to remove 1,1,2,2-tetrachloroethane,
Used for the next reaction.

Example 3 Polyolefin as a raw material had a melt index of 5.5 g /
The reaction was carried out in the same manner as in Example 2 except that high density polyethylene having a density of 0.963 g / cc was used, and then the product was separated.

The product had a pure white hue and analysis showed that the chlorinated polyethylene contained 37.3% chlorine. Mooney viscosity of raw rubber (ML1 + 4,1
(00 ° C.) was 46. The hue stability of the product was tested by an accelerated test by heat, but no change in hue was observed even after 10 days at 70 ° C.

Further, the product was kneaded according to the composition shown in Table 1 and the physical properties and vulcanized physical properties of the unvulcanized product were measured. This is summarized in Table 2.

On the other hand, 1, separated by a drum dryer
As a result of analysis, 0.3% of 1,2-trichloroethane was chlorinated and produced 1,1,2,2-tetrachloroethane. This 1,1,2-trichloroethane is distilled to remove 1,1,2,2-tetrachloroethane,
Used for the next reaction.

Example 4 Polyolefin as a raw material had a melt index of 5.0 g /
Min, a linear low density polyethylene (ethylene / butene 1 copolymer) with a density of 0.921 g / cc was used, and chlorine gas was changed to 6
Example 1 except that it was introduced at a flow rate of liter / minute for 85 minutes
The reaction was carried out in the same manner as, followed by separation of the product.

The product has a pure white hue, and as a result of analysis, this chlorinated ethylene-butene 1 copolymer was 27.1.
It was found to contain% chlorine. The Mooney viscosity (ML1 + 4,100 ° C.) of the raw rubber was 39. The hue stability of the product was tested by accelerated test by heat,
No change was observed in the hue even after 10 days.

Further, the product was kneaded according to the composition shown in Table 1, and the physical properties and vulcanized physical properties of the unvulcanized product were measured. This is summarized in Table 2.

On the other hand, 1, separated by a drum dryer
As a result of analysis, 1,2-trichloroethane was chlorinated at 0.2%, and 1,1,2,2-tetrachloroethane was produced. This 1,1,2-trichloroethane is distilled to remove 1,1,2,2-tetrachloroethane,
Used for the next reaction.

Example 5 Polyolefin as a raw material had a melt index of 6.0 g /
Min., The same method as in Example 1 except that ultra low density polyethylene (ethylene / α-olefin copolymer) having a density of 0.900 g / cc was used and chlorine gas was introduced at a flow rate of 6 liters / minute for 100 minutes. The reaction was carried out and the product was subsequently separated.

The product had a pure white hue, and as a result of analysis, this chlorinated ethylene / α-olefin copolymer was found to be 2
It was found to contain 9.9% chlorine. The Mooney viscosity (ML1 + 4,100 ° C.) of the raw rubber was 42. The hue stability of the product was tested by an accelerated test by heat.
No change in hue was observed even after 10 days at 0 ° C.

Further, the product was kneaded according to the composition shown in Table 1, and the physical properties and vulcanized physical properties of the unvulcanized product were measured. This is summarized in Table 2.

On the other hand, 1, separated by a drum dryer
As a result of analysis, 1,2-trichloroethane was chlorinated at 0.2%, and 1,1,2,2-tetrachloroethane was produced. This 1,1,2-trichloroethane is distilled to remove 1,1,2,2-tetrachloroethane,
Used for the next reaction.

Example 6 A commercial product containing 1,1,2-trichloroethane as a solvent and impurities 1-butanol and 1,2-epoxybutane (1,1,2-trichloroethane manufactured by Kanto Chemical Co., Inc.)
The reaction was carried out in the same manner as in Example 1 except that was used as it was, and then the product was separated.

The product was colored pale yellow and analysis showed that this chlorinated polyethylene contained 32.8% chlorine. Mooney viscosity of raw rubber (ML1 + 4,10
(0 ° C.) was 58. The hue stability of the product was tested by an accelerated test by heat, and after 5 days at 70 ° C., the product turned further brown.

Further, the product was kneaded according to the composition shown in Table 1, and the physical properties and vulcanized physical properties of the unvulcanized product were measured. This is summarized in Table 2. It shows that scorch time is short and scorch is easy.

Example 7 A commercial product containing 1,1,2-trichloroethane as a solvent and impurities 1-butanol and 1,2-epoxybutane (1,1,2-trichloroethane manufactured by Kanto Chemical Co., Inc.)
The reaction was performed in the same manner as in Example 4 except that was used as it was, and then the product was separated.

The product was colored pale yellow, and as a result of analysis, this chlorinated ethylene / butene 1 copolymer was 25.1%.
It was found to contain chlorine. Mooney viscosity of raw rubber (M
L1 + 4,100 ° C.) was 37. The hue stability of the product was tested by accelerated test by heat,
It turned brown even more as the days passed.

Further, the product was kneaded according to the composition shown in Table 1, and the physical properties and vulcanized physical properties of the unvulcanized product were measured. This is summarized in Table 2. It shows that scorch time is short and scorch is easy.

Example 8 Commercial product containing impurities 1,1-butanol and 1,2-epoxybutane in 1,1,2-trichloroethane as a solvent (1,1,2-trichloroethane manufactured by Kanto Chemical Co., Inc.)
The reaction was carried out in the same manner as in Example 5 except that was used as it was, and then the product was separated.

The product was colored pale yellow, and as a result of analysis, it was found that this chlorinated ethylene / α-olefin contained 27.7% chlorine. Mooney viscosity of raw rubber (ML
1 + 4,100 ° C.) was 40. The hue stability of the product was tested by an accelerated test by heat, and after 5 days at 70 ° C., the product turned further brown.

Further, the product was kneaded according to the formulation shown in Table 1 and the physical properties and vulcanized physical properties of the unvulcanized product were measured. This is summarized in Table 2. It shows that scorch time is short and scorch is easy.

[0052]

[Table 2] As is clear from the above Examples and Comparative Examples, the chlorinated polyolefin obtained in the present invention has a pure white hue and is also highly stable in scorch and has high commercial value. I understand.

[0053]

As is apparent from the above description, the present invention establishes an industrial manufacturing process which does not have a bad influence on the ozone layer existing in the stratosphere of the earth, and the chlorination obtained by the present invention. Polyolefin is a product in which coloring of 1,2,3-trichloroethane containing an alcohol compound and / or an epoxy compound as an impurity as a solvent is improved, and stability of scorch is improved. It is possible to increase the intellectual value.

Claims (3)

[Claims] 1. When carrying out a chlorination reaction of a polyolefin dissolved or suspended in a solvent using a radical generator as a catalyst and chlorine gas or sulfuryl chloride, 1,1,2-trichloroethane is used as the solvent. A method for producing a chlorinated polyolefin, which is characterized by being used. 2. The solvent used is an alcohol compound and / or
Alternatively, the production method according to claim 1, which is 1,1,2-trichloroethane containing no epoxy compound. 3. A chlorinated polyolefin produced by the reaction is separated from a solvent, and then a chlorine adduct of the solvent, which is a by-product of the solvent, is removed to the outside of the system to obtain 1,1,2-trichloroethane. The method according to claim 1 or 2, which is used again in the reaction.