JPS6024802B2 - Method for producing chlorinated polyolefin - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for producing chlorinated polyolefin.

More specifically, in producing a chlorinated polyolefin by chlorinating a powdered polyolefin in an aqueous suspension system, the agent selected from sulfonated styrenic polymers and metal salts thereof is used as an anti-agglomeration agent for the product. The present invention relates to a method for producing a chlorinated polyolefin, characterized in that at least one compound, or a compound [B] and a penetrating surfactant are added to the reaction system. It is known to carry out aqueous suspension chlorination of polyolefins at elevated temperatures and in the presence of surfactants.

However, when producing rubber-like chlorinated polyolefin using these conventional methods, the chlorination reaction must be carried out at a reaction temperature close to the melting point of the raw polyolefin, so the surface of the polyolefin particles remains in a semi-molten state. As a result, each particle adheres to each other and forms agglomerates, making operation difficult.

Furthermore, if particles agglomerate during the reaction, uniform chlorination thereafter becomes impossible, making it difficult to produce a soft, rubber-like chlorinated polyolefin. The chlorinated polyolefin produced in this way has a large and uneven particle size, and even after washing and drying, acid content and other impurities contained in the agglomerated particles are incompletely removed, so it is difficult to mold it. Sometimes coloration occurs, exhibiting reduced thermal stability and other defects.

Furthermore, when a product with such non-uniform particle size is mixed with other resin components, poor dispersion tends to occur, which is an obstacle to producing a blended resin with excellent properties.

Such agglomeration of particles can be prevented by lowering the reaction temperature, but in that case, only a chlorinated polyolefin with less rubbery properties can be obtained. Although it is possible to prevent agglomeration by extremely reducing the amount of polyolefin charged into the reactor, this method is uneconomical and disadvantageous. Furthermore, as a method to alleviate the above-mentioned difficulties, it is known that relatively inert substances such as polyvinyl chloride (PVC) powder or inorganic powders such as silicon oxide, talc, and clay are added to the aqueous suspension system. It is being

However, this method is ineffective unless a large amount of the above-mentioned additives are added, and this method has the disadvantage that large amounts of these additives are mixed into the product, which inevitably limits the use of the product. . Therefore, methods have been proposed to prevent polyolefin particles from coagulating with each other by coexisting dispersants such as polyvinyl alcohol and surfactants such as ethylene oxide/propylene oxide block polymers in the suspension. .

However, when polyvinyl alcohol is added to the suspension, the chlorinated polyvinyl alcohol is mixed into the chlorinated polyolefin, so when this chlorinated polyolefin is heat-processed, significant thermal deterioration occurs. However, it has the disadvantage that the product becomes colored. On the other hand, when a normal surfactant such as ethylene oxide/propylene oxide block polymer is added to the suspension to carry out the chlorination reaction of polyolefin, hydrochloric acid generated during the chlorination reaction, As the surfactant is gradually decomposed and consumed by the action of hypochlorous acid, its dispersion ability decreases and particles often form into agglomerates. Therefore, in these methods, this decomposed amount is added during the reaction, or
Alternatively, if a large amount is used from the beginning of the reaction, agglomeration can be prevented to some extent, but the effect is not sufficient, and the thermal stability of the product is significantly reduced due to the use of large amounts of dispersants and surfactants. There are some difficulties. As mentioned above, the selection of a dispersant or surfactant in the production of chlorinated polyolefins is an important issue, and it is important to select a dispersant or surfactant that does not adversely affect the physical properties of the product, such as the thermal stability and coloration of the product, and is economically satisfactory. Dispersants and surfactants are still unknown.

As a result of various studies on surfactants used in producing chlorinated polyolefins in an aqueous suspension system, the present inventors found that at least one compound selected from sulfonated products of wind styrene polymers and metal salts thereof. , or {B' It has been found that a combination system of the compound and a penetrating surfactant has extremely excellent stability and dispersion power even under the harsh conditions when producing chlorinated polyolefin. In other words, if such a surfactant is added to the reaction system, it acts as an excellent anti-agglomeration agent, and prevents particle agglomeration even under severe conditions such as high temperatures and the presence of high hydrochloric acid and high hypoxic acid. It has been found that a chlorinated polyolefin in the form of fine and uniform particles can be obtained, which has extremely excellent stability and dispersibility, and also has a fast reaction between polyolefin and chlorine. According to the present invention, particle agglomeration does not occur during the reaction, which facilitates operation and allows product discharge, transportation, acid washing, drying, and other processing steps to be carried out easily and economically. can. Moreover, since a white, fine powder product of excellent quality is obtained, it can be easily blended with other resins without the need for any special process.

Moreover, the product after heat processing also has very little coloring, which is extremely advantageous for obtaining light-colored molded products.

According to the present invention, since there is no fear of particle agglomeration during the reaction, it is possible to increase the amount of polyolefin charged to 2 to 3 times that of the conventional method, and its industrial effects are great.

Examples of the styrene polymer used in the sulfonated styrenic polymer or its metal salt used as an anti-agglomeration agent in the present invention include styrene, Q-substituted styrene such as Q-methylstyrene, vinyltoluene, and -chlorostyrene. Polymers of styrene derivatives such as substituted styrene, and monomers mainly composed of these monomers and copolymerizable therewith, such as isobutylene, acrylonitrile, acrylic acid and methacrylic acid, and their methyl or ethyl esters. Mutual polymers obtained from monomer polymers obtained by mixing one or more monomers such as vinyl or vinylidene compounds, vinyl heterocyclic compounds such as vinylpyridine and vinylcarbazole, and conjugated diene compounds such as butadiene and isoprene. Combination can be mentioned.

These sulfonated styrene polymers can be produced, for example, as follows. Styrenic polymer and sulfuric acid are mixed and heated under heating to a temperature of about 35 to 110 qo for 2 to 1 hour. After cooling, the polymer is reacted with sulfuric acid and washed with water to obtain a sulfonated styrenic polymer. Furthermore, the metal of the metal salt of the styrene polymer sulfonate used as the agglomeration inhibitor in the present invention is selected from alkali metals and alkali metals, and preferably lithium, sodium, potassium, and calcium. can give.

These metal salts of styrenic polymer sulfonates can be easily obtained by mixing and reacting the styrenic polymer sulfonates with the above-mentioned metal compounds, and washing the polymer with water in a furnace for 8U. In some cases, at least one selected from sulfonated products of styrene derivatives and metal salts thereof
A sulfonated product of a styrenic polymer obtained by polymerizing a monomer, or a monomer polymer consisting mainly of these monomers and a monomer that can be copolymerized with it, or a metal salt thereof. May be used. The molecular weight of these sulfonated styrenic polymers and their metal salts is 500 to 1000.
A value of 0 is preferable, and a value of 1000 to 5000 is more preferable.

The amount of the agglomeration inhibitor of the present invention added is 0.01 to 3% by weight, preferably 0.1 to 1% by weight based on the polyolefin.
Weight%. On the other hand, common penetrating surfactants that can be used in combination with the anti-boiling agent in the present invention include alcohol or phenol adducts of polyoxyethylene such as polyoxyethylene nonylphenyl ether, and ethylene oxyethylene. Dope.

Examples include nonionic surfactants such as pyrene oxide block polymers, surfactants such as sodium alkylbenzenesulfonates, alcohol sulfates, alkylsulfonic acids, alkylarylsulfonic acids, or their sodium salts. The amount of penetrating surfactant added is 0.01 to 3% by weight, preferably 0.01 to 3% by weight, based on the polyolefin.
It is 1 to 1% by weight.

The polyolefin used in the present invention may be any finely powdered polyolefin, and can be used regardless of its molecular weight.

As the conditions for chlorination, the conditions of conventional methods can be applied as they are. Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 120 In the autoclave was added water 80Z and powdered polyethylene 16K9 (melt index 22 density 0.9).
57).

After adding 100 μm of sodium polyoxyethylene alkylphenyl ether sulfate as a penetrating surfactant and 60 μm of sodium polystyrene sulfonate having a molecular weight of 200 as an anti-agglomeration agent, chlorine gas was added at a reaction temperature of 120°C. The reaction was carried out for 6 hours. The obtained chlorinated polyethylene had a particle size of 2 sides or less and was extremely uniform particles. Furthermore, it did not show any coloring after washing with water and drying, and did not change color even during heat processing.

The chlorine content of this chlorinated polyethylene is 4% by weight, and the cutting strength according to JISK-6723 is 100k9/
The elongation was 800%, and the 100% modulus was 12k9/m. Note that similar results were obtained when a potassium salt of polystyrene sulfonic acid having a molecular weight of 2200 was used as the agglomeration inhibitor.

Example 2 In place of the sodium polyoxyethylene alkyl phenyl ether sulfate in Example 1, sodium alkylbenzene sulfonate was used and chlorination was carried out for 7 hours using the same recipe and method as in Example 1.

The obtained chlorinated polyethylene has a particle size of 2 sides or less,
They were extremely uniform white particles. The chlorine content of this chlorinated polyethylene is 4% by weight, and its cutting strength is:
At 80 kg/, the elongation was 900% and the 100% modulus was 10k9/. Example 3 Polyoxyethylene nonylphenyl ether was used instead of sodium polyoxyethylene alkylphenyl ether sulfate in Example 1, and chlorination was carried out for 6 hours using the same recipe and method as in Example 1. .

The obtained chlorinated polyethylene had a particle size of 2 or less and was extremely uniform white particles. In addition, the chlorine content of this chlorinated polyethylene is 40%, and its cutting strength is 1
It was 20k9/ground, elongation was 750%, and 100% modulus was 14k9/ground. Example 4120 Into the autoclave are charged 80 g of water and powdered polyethylene 16k9 (melt index 10, density 0.960).

After adding 100 ml of sodium alkylbenzenesulfonate as a penetrating surfactant and 60 ml of sodium polystine sulfonate having a molecular weight of 2600 as an anti-agglomeration agent, the reaction was carried out for 7 hours at a reaction temperature of 110 to 125°C by passing chlorine gas through the mixture. Ta. The obtained chlorinated polyethylene was extremely uniform particles with a particle size of 2 ribs or less. Furthermore, there was no coloration after the water washing and drying process, and there was almost no discoloration during heat processing. The chlorine content of the thus obtained chlorinated polyethylene was 36%, the cutting strength was 110k9/mm, the elongation was 1000%, and the 100% modulus was 9k9/mm. Example 5 In Example 4, chlorination was carried out for 6 hours using the same recipe and method as in Example 4, except that sodium alkylbenzenesulfonate was not used.

The obtained chlorinated polyethylene is extremely uniform white particles with a particle size of 2 mm or less, and even after a washing and drying process,
No coloration was observed, no discoloration occurred during heat processing, and an extremely white molded product was obtained. The chlorine content of this chlorinated polyethylene is 36%, and the cutting strength is 130k9/yo,
The elongation was 600% and the 100% modulus was 20 kg/. Comparative Example 1 Chlorination was carried out in the same manner as in Example 1, except that only sodium polyoxyethylene alkylphenyl ether sulfate 1009 was used as a surfactant, and the amount of polyethylene charged was 8 kg. After about 2 hours, agglomeration of the reaction particles occurred and operation became impossible.

Comparative Example 2 Only sodium alkylbenzenesulfonate was used as a surfactant, and the amount of polyethylene charged was 5k.
9 and chlorination was carried out in the same manner as in Example 1 except for the above, but agglomeration of the reaction particles occurred after about 5 hours, and the reaction was discontinued.

Approximately 50% of the chlorinated polyethylene after the reaction had a particle size of 20 to 5 ribs, and the particle size was also nonuniform. The chlorine content of this chlorinated polyethylene is 38%, and the cutting strength is 15%.
0k9/ground, elongation is 300%, 100% modulus is 7
It was 0k9/ground. Comparative Example 3 Chlorination was carried out in the same manner as in Example 1 except that only polyoxyethylene nonyl phenyl ether 100% was used as a surfactant and the amount of polyethylene was 8k9. However, after about 3 hours, agglomeration of the reaction particles occurred and operation became impossible.

Example 6 In Example 2, highly crystalline polypropylene (Melt Flow Intex 1.0, softening temperature 150°C, particle size 0.1 to 0.5 side) was used instead of powdered polyethylene, and the reaction temperature was set to 145°C. Chlorination was carried out for 4 hours in the same manner as in Example 2, except that it was carried out at a temperature of 0 to 15 hours.

The particles after the reaction were uniform particles with two or fewer sides, and the chlorine content was 30%. Example 7 Chlorination was carried out for 8 hours in the same manner as in Example 1, except that 20 kg of medium density polyethylene powder (high road melt index 2.0) was used instead of the polyethylene in Example 1. .

The particles after the reaction are uniform particles with 2 sides or less, and the chlorine content is 4.
It was 0%. The cutting strength of this was 100k9/m, the elongation was 800%, and the 100% modulus was 10k9/m. Example 8 In Example 1, polystyrene sulfonic acid having a molecular weight of about 2000 was used instead of sodium polystyrene sulfonate, and chlorination was carried out for 7 hours using the same recipe and method as in Example 1.

The obtained chlorinated polyethylene had a particle size of 2 legs or less and was extremely uniform white particles. The chlorine content of this chlorinated polyethylene is 40%, and its cutting strength is 90 kg.
/'s elongation is 850%, 100% modulus is 11k9
/ It was me. Example 9 In Example 1, sodium sulfonate of isoptylene-styrene copolymer having a molecular weight of about 3000 was used instead of sodium polystyrene sulfonate, and chlorination was carried out using the same recipe and method as in Example 1. Time went.

Claims (1)

[Claims] 1. In producing chlorinated polyolefin by chlorinating powdered polyolefin in an aqueous suspension system, (A) sulfonated styrenic polymer and its metal salt are used as an agglomeration inhibitor for reactant particles. A method for producing a chlorinated polyolefin, which comprises adding at least one selected compound, or (B) the compound and a penetrating surfactant to a reaction system.