JPH06145226A - Production of chlorosulfonated polyolefin - Google Patents

Abstract

PURPOSE:To establish an industrial production for producing a chlorinated polyolefin without manifesting adverse effects on the ozonosphere present in the stratosphere of the earth by using a specific solvent. CONSTITUTION:This method comprises using octamethylcyclotetrasiloxane as a solvent in carrying out the chlorination or the chlorination and chlorosulfonation of a polyolefin dissolved or suspended in the solvent with chlorine and sulfurous acid gas, the chlorine and sulfuryl chloride, the sulfuryl chloride alone or three reagents of the chlorine, sulfurous acid gas and sulfuryl chloride or the sulfuryl chloride and sulfurous acid gas using a radical former as a catalyst.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a process for producing chlorosulfonated polyolefin. More specifically, it relates to a production method for producing a chlorosulfonated polyolefin by dissolving or suspending a polyolefin in octamethylcyclotetrasiloxane and carrying out a chlorination and chlorosulfonation reaction.

[0002]

BACKGROUND OF THE INVENTION It is known to dissolve or suspend a polyolefin in a solvent to produce a chlorosulfonated 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” conducted in June 1990, carbon tetrachloride became a regulated substance, and as a result, since 1995, tetrachloride for commercial production of chlorosulfonated polyolefins has been changed. The use of carbon has been difficult. Therefore, a new method for producing a chlorosulfonated polyolefin that does not use carbon tetrachloride has been desired.

[0003]

SUMMARY OF THE INVENTION From the viewpoint of protecting the global environment, the present invention uses octamethylcyclotetrasiloxane having a low ozone depletion potential (ODP) as a solvent and is a process for producing a chlorosulfonated polyolefin having commercial value. The purpose is to provide.

[0004]

That is, the present invention is a polyolefin dissolved or suspended in a solvent, with a radical generator as a catalyst, chlorine and sulfurous acid gas, chlorine and sulfuryl chloride,
Sulfuryl chloride alone or three reagents of chlorine, sulfurous acid gas and sulfuryl chloride, in the reaction of chlorination or chlorination and chlorosulfonation using sulfuryl chloride and sulfurous acid gas, characterized by using octamethylcyclotetrasiloxane as a solvent The present invention relates to a method for producing a chlorosulfonated polyolefin. The details will be described below.

[0005]

The solvent used in the present invention has an ozone depletion potential (O
Octamethylcyclotetrasiloxane having a low DP) is used.

The reaction of chlorination and chlorosulfonation uses a radical generator as a catalyst, chlorine and sulfurous acid gas, chlorine and sulfuryl chloride, sulfuryl chloride alone, or three reagents of chlorine, sulfurous acid gas and sulfuryl chloride, sulfuryl chloride and sulfurous acid. The gas is reacted with a polyolefin dissolved or suspended in octamethylcyclotetrasiloxane. When sulfuryl chloride is added, an amine compound such as pyridine or quinoline is added as a promoter if necessary. The reaction temperature is 40 to 150 ° C, preferably 60 to 1
It is 30 ° C., and the reaction pressure is 0 to 10 kg / cm ² , preferably 0 to 7 kg / cm ² .

As the radical generator, an azo compound or an organic peroxide is used. Examples of the azo compound include α, α′-azobisisobutyronitrile, azobiscyclohexanecarbonitrile, and 2,2′-azobis (2,4-dimethylvaleronitrile), and the organic peroxide is a peroxide. Examples thereof include benzoyl oxide, acetyl peroxide, t-butyl peroxide, and t-butyl perbenzoate. Of these, azo compounds are preferable,
Particularly preferred is α, α′-azobisisobutyronitrile.

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).

After completion of the reaction, hydrogen chloride and sulfurous acid gas remaining in the reaction solution are removed by introducing nitrogen, and a stabilizer is added if necessary. The stabilizer is preferably an epoxy compound such as 2,2'-bis (4-glycidyloxyphenyl) propane.

Known methods for separating the product polymer from the solvent include steam distillation, a drum dryer, and a vented extruder, and these methods are used to separate the two.

The chlorosulfonated polyolefin referred to in the present invention includes, for example, chlorosulfonated polyethylene, chlorosulfonated ethylene / propylene copolymer, chlorosulfonated ethylene / butene copolymer according to the kind of the raw material polyolefin as described above. , Chlorosulfonated ethylene-hexene copolymer, chlorosulfonated ethylene
Examples thereof include 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,
Compounding agents for rubber or resin such as plasticizers, processing aids, anti-aging agents or vulcanization accelerators such as TRA and TT can be mentioned. Vulcanization methods include steam vulcanization, UHF vulcanization, hot air vulcanization,
A general method such as injection, molding, or rotocure may be used.

For the end use, like the existing chlorosulfonated polyolefin, automobile hoses, gas hoses, industrial hoses, escalator handrails, electric wires, leisure boats, roofing, pond liners, rolls, belts,
Boots, packings, sheets, pull cloths, adhesives, paints, sealants and the like can be mentioned.

[0014]

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 are obtained according to the following measuring methods.

Amount of chlorine and sulfur: Combustion flask method Unvulcanized rubber Physical properties: JIS K 6300 Vulcanized rubber properties: JIS K 6301 Color of product: Visual inspection.

Example 1 28 kg of octamethylcyclotetrasiloxane was placed in a 30-liter glass-lined autoclave, melt index was 6.2 g / 10 min, and density was 0.95 g / c.
2.8 kg of high-density polyethylene (c) was charged.

After adding 0.3 g of pyridine as a co-catalyst for the chlorosulfonation reaction, steam was passed through the jacket of the reactor and maintained at 120 ° C. for 2 hours to uniformly dissolve polyethylene. 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.

14 g of α, α'-as a radical initiator
Azobisisobutyronitrile was dissolved in 2.9 kg of octamethylcyclotetrasiloxane. While continuously adding this solution to the reactor, the reaction was carried out by adding 5.9 kg of sulfuryl chloride to the reactor from another charging port. The reaction time required 3 hours. The pressure in the reactor was maintained at 3.0 kg / cm ² during the reaction.

After the reaction was completed, the pressure was returned to normal pressure and the temperature of the reactor was lowered to 70 ° C. Thereafter, nitrogen was introduced while maintaining the temperature at 70 ° C., and the sulfurous acid gas and hydrogen chloride gas remaining in the reaction solution were removed.

As a stabilizer, 43 g of 2,2'-bis (4
-Glycidyloxyphenyl) propane,
This solution was fed to a drum dryer heated to 210 ° C. to separate chlorosulfonated polyethylene as a product from the solvent.

The product had a pure white hue and analysis showed that the chlorosulfonated polyethylene contained 35.1% chlorine and 1.2% sulfur. The Mooney viscosity (ML _{1 + 4} , 100 ° C.) of the raw rubber was 51.

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 vulcanized physical properties such as tensile strength were measured.

The values obtained are summarized in Table 2 below.

Example 2 A raw material polyolefin having a melt index of 0.85 g
/ Min, the reaction was performed in the same manner as in Example 1 except that high density polyethylene having a density of 0.965 g / cc was used, and then the product was separated.

The product had a pure white hue and analysis showed that the chlorosulfonated polyethylene contained 33.7% chlorine and 1.2% sulfur. The Mooney viscosity (ML _{1 + 4} , 100 ° C.) of the raw rubber was 111.

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.

Example 3 Polyolefin as a raw material had a melt index of 4.8 g /
Min, a high density polyethylene having a density of 0.963 g / cc was used, and the reaction was performed in the same manner as in Example 1 except that the amount of sulfuryl chloride added was changed to 3.4 kg, and then the product was separated.

The product had a pure white hue and analysis showed that the chlorosulfonated polyethylene contained 23.3% chlorine and 1.1% sulfur. The Mooney viscosity (ML _{1 + 4} , 100 ° C.) of the raw rubber was 33.

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.

[0033]

[Table 1]

[0034]

[Table 2]

[0035]

As is clear from the above description, the present invention establishes an industrial production process for chlorosulfonated polyolefins that does not adversely affect the ozone layer existing in the stratosphere of the earth.

Claims (1)

[Claims] 1. A polyolefin dissolved or suspended in a solvent, using a radical generator as a catalyst, chlorine and sulfurous acid gas, chlorine and sulfuryl chloride, sulfuryl chloride alone, or chlorine, sulfurous acid gas and sulfuryl chloride, three reagents, and chlorine. A method for producing a chlorosulfonated polyolefin, characterized in that octamethylcyclotetrasiloxane is used as a solvent in the reaction of chlorination or chlorination and chlorosulfonation using sulfuryl and sulfurous acid gas.