JPH06345851A - Heat stabilizer for halogen-containing polymer - Google Patents

Abstract

PURPOSE:To produce the subject heat stabilizer composed of a specified epoxy- modified block copolymer, excellent in prolongation of service life of a molding machine, exhibiting an excellent moldability, capable of producing a molding excellent in surface properties and flexibility and useful for production of a film, a leather, a water-proofing agent, etc. CONSTITUTION:This heat stabilizer is composed of an epoxy-modified block copolymer synthesized by epoxidizing double bonds of a diene compound in a block copolymer containing (A) a polymer block composed mainly of an aromatic vinyl compound and (B) a polymer block composed mainly of a conjugated diene compound. In addition, in the case the heat stabilizer is added to a halogen-containing polymer, the ratio of the epoxy-modified block copolymer is 0.1 to 10wt.%, preferably 1 to 5wt.% based on the halogen-containing polymer.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to excellent heat stabilizers for halogen-containing polymers.

[0002]

2. Description of the Related Art Epoxidized soybean oil or bisphenol has hitherto been used as a trapping agent for acidic substances such as hydrochloric acid gas generated during thermal processing of halogen-containing polymers such as polyvinyl chloride, chlorinated paraffin, chloroprene rubber and chlorinated rubber. Type epoxy is used (Japanese Patent Application Laid-Open No. 57-158260).
issue).

[0003]

However, since these heat stabilizers have insufficient capacities for capturing acidic substances,
It has the drawback that sufficient processing time cannot be taken during high temperature processing of halogen-containing polymers. As a result, the transparency of the polymer is adversely affected, and since the kneading time cannot be sufficiently taken, a film or the like produced from the polymer is apt to be damaged. There is also a problem that a molding machine or the like is corroded by an acidic substance such as chlorine gas or hydrochloric acid that is decomposed and produced during thermal processing of the halogen-containing polymer.

[0004]

OBJECTS OF THE INVENTION It is an object of the present invention to improve the drawbacks of these conventionally used heat stabilizers for halogen-containing polymers and to provide more excellent heat stabilizers.

[0005]

The present invention provides (a) a polymer block (A) mainly containing a vinyl aromatic compound and a polymer block (B) mainly containing a conjugated diene compound in the same molecule. A heat stabilizer for a halogen-containing polymer comprising an epoxy-modified block polymer obtained by epoxidizing a double bond of unsaturated carbon of a conjugated diene compound of the block copolymer.

Examples of the vinyl aromatic compound of the block polymer used in the present invention include styrene, α-methylstyrene, vinyltoluene, p-tertiary butylstyrene, divinylbenzene, p-methylstyrene and 1,1-.
One kind or two or more kinds can be selected from diphenylstyrene and the like, and styrene is preferable. Examples of the conjugated diene compound include butadiene, isoprene,
1 of 1,3-pentadiene, 2,3-dimethyl-1,3-butadiene, piperylene, 3-butyl-1,3-octadiene, phenyl-1,3-butadiene, etc.
One kind or two or more kinds are selected, and among them, butadiene, isoprene and a combination thereof are preferable.

The block copolymer referred to herein is a block copolymer composed of a polymer block A containing a vinyl aromatic compound as a main component and a polymer block B containing a conjugated diene compound as a main component. The copolymerization ratio of the group compound and the conjugated diene compound is 5/95 to 70/30, and the polymerization ratio of 10/90 to 60/40 is particularly preferable.

The number average molecular weight of the block copolymer used in the present invention is 5,000 to 600,000, preferably 1.
It is in the range of 0000 to 500,000, and the molecular weight distribution [ratio of weight average molecular weight (Mw) to number average molecular weight (Mn) (Mw / Mn)] is 10 or less. The molecular structure of the block polymer may be linear, branched, radial, or any combination thereof.

For example, A-B-A, B-A-B-A,
(A-B-) ₄ is a vinyl aromatic compound-conjugated diene compound block polymer having a structure such as Si and A-B-A-B-A. Further, the unsaturated bond of the conjugated diene compound of the block polymer may be partially hydrogenated, and the hydrogenation of the conjugated diene compound has an unsaturation degree of 5% or more, preferably 10% or more.

As the method for producing the block polymer used in the present invention, any method can be used as long as it has the above-mentioned structure. For example, Japanese Patent Publication No. 40-2
According to the method described in Japanese Patent No. 3798, a vinyl aromatic compound-conjugated diene compound block copolymer can be synthesized in an inert solvent using a lithium catalyst or the like.
Further, Japanese Patent Publication No. 42-8704 and Japanese Patent Publication No. 43-6
No. 636 or the method described in JP-A-59-133203, hydrogenation is carried out in the presence of a hydrogenation catalyst in an inert solvent, and the partially hydrogenated block used in the present invention is used. Polymers can be synthesized.

In the present invention, the epoxy-modified block copolymer used in the present invention can be obtained by epoxidizing the above block copolymer.

The epoxy-modified block copolymer in the present invention can be obtained by reacting the above block copolymer with an epoxidizing agent such as hydroperoxides and peracids in an inert solvent. Examples of peracids include formic acid, peracetic acid, perbenzoic acid and trifluoroperacetic acid. Of these, peracetic acid is a preferred epoxidizing agent because it is industrially produced in large quantities, is inexpensively available, and has high stability.

Hydroperoxides include hydrogen peroxide, tertiary butyl hydroperoxide, cumene peroxide and the like.

A catalyst may be used in the epoxidation, if necessary.

For example, in the case of peracid, an alkali such as sodium carbonate or an acid such as sulfuric acid can be used as a catalyst. In the case of hydroperoxides, a catalytic effect can be obtained by using a mixture of tungstic acid and caustic soda with hydrogen peroxide, an organic acid with hydrogen peroxide, or molybdenum hexacarbonyl with tertiary butyl hydroperoxide. You can

There is no strict regulation on the amount of epoxidizing agent,
The optimum amount in each case will depend on such variables as the particular epoxidizing agent used, the degree of epoxidation desired, the particular block copolymer used, and the like.

The inert solvent can be used for the purpose of decreasing the viscosity of the raw material and stabilizing it by diluting the epoxidizing agent. In the case of peracetic acid, aromatic compounds, ethers, esters and the like can be used. Can be used. Particularly preferred solvents are hexane, cyclohexane, toluene, benzene, ethyl acetate, carbon tetrachloride, chloroform. There are no strict restrictions on the epoxidation reaction conditions. The reaction temperature range that can be used depends on the reactivity of the epoxidizing agent used. For example, in the case of peracetic acid, 0 to 70 ° C. is preferable, below 0 ° C. the reaction is slow, and above 70 ° C., decomposition of peracetic acid occurs. In addition, tertiary butyl hydroperoxide, which is an example of hydroperoxide,
In the molybdenum dioxide diacetylacetonate system, 20 ° C to 150 ° C is preferable for the same reason. No special manipulation of the reaction mixture is necessary, for example the mixture may be stirred for 2-10 hours. Isolation of the obtained epoxy-modified copolymer by a suitable method, for example, a method of precipitating with a poor solvent, a method of adding the polymer into hot water under stirring and distilling off the solvent, a direct desolvation method, etc. It can be carried out.

Examples of the halogen-containing polymer used in the present invention include a vinyl chloride homopolymer, a vinyl chloride-vinyl acetate copolymer, a vinyl chloride-ethylene vinyl acetate copolymer, and a vinyl chloride-ethylene copolymer. , Vinyl chloride-propylene copolymer, vinyl chloride-styrene copolymer, vinyl chloride-isobutylene copolymer,
Vinyl chloride-vinylidene chloride copolymer, vinyl chloride-urethane copolymer, vinyl chloride-acrylic acid ester copolymer, vinyl chloride-styrene-maleic anhydride terpolymer, vinyl chloride-styrene-acrylonitrile copolymer , Vinyl chloride-butadiene copolymer, vinyl chloride-isoprene copolymer, vinyl chloride-chlorinated propylene copolymer, vinyl chloride-vinylidene chloride-vinyl acetate copolymer, vinyl chloride-maleic acid ester copolymer, chlorinated Vinyl-methacrylic acid ester copolymers, vinyl chloride-acrylonitrile copolymers, vinyl chloride copolymers such as vinyl chloride-maleimide copolymers, and α of such resins as polyethylene, polypropylene, polybutene and poly-3-methylbutene. -Olefin polymer or ethylene-vinyl acetate copolymer Polymers, polyolefins such as ethylene-propylene copolymers and their copolymers, polystyrenes, acrylic resins, polyurethanes, copolymers of styrene with other monomers (eg maleic anhydride, butadiene, acrylonitrile, etc.), acrylonitrile -Styrene-butadiene copolymers, acrylic acid ester-styrene-butadiene copolymers, methacrylic acid ester-styrene-butadiene copolymers, and blended products can be used.

When the heat stabilizer of the present invention is added to a halogen-containing polymer, the epoxy-modified block copolymer is usually contained in an amount of 0.1 to 10% by weight, preferably 1
~ 5% by weight. If the addition amount is less than 0.1% by weight, the absorption of the above-mentioned acidic substance is not sufficient, and 10
If it exceeds 5% by weight, the physical properties of the polymer are adversely affected.

However, when the purpose of modifying the polymer is 50% by weight based on the halogen-containing polymer.
Up to the epoxy modified block copolymer can be added. In the heat stabilizer of the present invention, in addition to the above-mentioned active ingredients, auxiliary ingredients such as stearates can be appropriately added.

[0021]

The use of the heat stabilizer for a halogen-containing polymer of the present invention makes it possible to reduce the amount of acidic substances generated during high temperature processing of the polymer, and as a result, the life of a molding machine can be shortened as compared with the conventional case. Can also be extended. Also,
Since the molding time of the polymer can be taken longer than in the case where the conventional heat stabilizer is added, the moldability of the obtained product is improved, and the flexibility of the product is also improved. Therefore,
The halogen-containing polymer to which the heat stabilizer of the present invention is added can be advantageously used for production of industrial products such as films and leathers, waterproofing agents, wire coating materials, injection molded products and the like.

Next, the present invention will be described in detail with reference to examples. The examples are representative of the invention but do not limit the scope of the invention.

[Preparation of Epoxy-Modified Block Polymer] <Production Example 1> A polystyrene-polybutadiene-polystyrene block copolymer [Nippon Synthetic Rubber Co., Ltd.] was added to a jacketed reactor equipped with a stirrer, a reflux condenser and a thermometer. ), Trade name: TR2000] 300 g, and ethyl acetate 1500 g were charged and dissolved.

Then, a 30 wt% ethyl acetate solution of peracetic acid 1
69 g was continuously added dropwise, and the epoxidation reaction was carried out at 40 ° C. for 3 hours with stirring. The reaction solution was returned to room temperature and taken out from the reactor, a large amount of methanol was added to precipitate a polymer, and the polymer was filtered, washed with water and dried to obtain an epoxy-modified polymer. The obtained epoxy-modified polymer is referred to as polymer A (epoxy equivalent of polymer 470).

<Production Example 2> 300 g of a polystyrene-polybutadiene-polystyrene block copolymer [manufactured by Nippon Synthetic Rubber Co., Ltd., trade name: TR2000] in a jacketed reactor equipped with a stirrer, a reflux condenser and a thermometer. ,
1500 g of ethyl acetate was charged and dissolved.

Then, a 30 wt% ethyl acetate solution of peracetic acid 1
13 g was continuously added dropwise, and the epoxidation reaction was carried out at 40 ° C. for 3 hours with stirring. The reaction solution was returned to room temperature and taken out from the reactor, a large amount of methanol was added to precipitate a polymer, and the polymer was filtered, washed with water and dried to obtain an epoxy-modified polymer. The obtained epoxy-modified polymer is referred to as polymer B (epoxy equivalent of polymer: 698).

<Production Example 3> A block copolymer of polystyrene-polybutadiene-polystyrene in a jacketed reactor equipped with a stirrer, a reflux condenser, and a thermometer [Shell Chemical Co., Ltd., trade name: Califlex D1122].
300 g and 1500 g of cyclohexane were charged and dissolved. Then, 177 g of a 30 wt% ethyl acetate solution of peracetic acid
Was continuously added dropwise, and the epoxidation reaction was carried out at 40 ° C. for 3 hours with stirring.

The reaction solution was returned to room temperature and taken out from the reactor, a large amount of methanol was added to precipitate the polymer, and the polymer was filtered, washed with water and dried to obtain an epoxy-modified polymer. The obtained epoxy-modified polymer is referred to as polymer C (epoxy equivalent of polymer 445).

<Production Example 4> A polystyrene-polyisoprene-polystyrene block copolymer was added to a jacketed reactor equipped with a stirrer, a reflux condenser, and a thermometer [Shell Chemical Co., Ltd., trade name: Califlex D1122]. ]
300 g and 1500 g of cyclohexane were charged and dissolved. Then, 222 g of a 30 wt% ethyl acetate solution of peracetic acid
Was continuously added dropwise, and the epoxidation reaction was carried out at 40 ° C. for 3 hours with stirring.

The reaction solution was returned to room temperature and taken out from the reactor. A large amount of methanol was added to precipitate the polymer, which was filtered, washed with water and dried to obtain an epoxy-modified polymer. The obtained epoxy-modified polymer is referred to as polymer D (epoxy equivalent of polymer: 356).

<Production Example 5> Polystyrene-polyisoprene-was placed in a jacketed reactor equipped with a stirrer and a thermometer.
Block copolymer of polystyrene [Nippon Synthetic Rubber Co., Ltd.
Made, trade name: TR2000] 300 g, cyclohexane 150
0 g was charged and dissolved, and the temperature was 60 ° C.
p-Tolylbis (1-cyclopentadienyl) titanium / cyclohexane solution (concentration 1 mmol / l) 40
2.0 ml / c of 0 ml of n-butyllysium solution (concentration 5 mmol / l) and 8 ml of n-butyllithium solution
Add a mixture under pressure of hydrogen of m ² , hydrogen partial pressure 2.
The reaction was carried out at 5 kg / cm ^{2 for} 30 minutes. The solvent was removed from the obtained partially hydrogenated polymer (hydrogenation rate of the entire butadiene portion of 30%) solution by drying under reduced pressure.

300 g of this partially hydrogenated polymer and 1500 g of cyclohexane were charged and dissolved. Then 30 of peracetic acid
300 g of a wt% ethyl acetate solution was continuously added dropwise, and an epoxidation reaction was carried out at 40 ° C. for 3 hours with stirring.

The reaction solution was returned to room temperature and taken out of the reactor. A large amount of methanol was added to precipitate the polymer, which was filtered, washed with water and dried to obtain an epoxy-modified polymer. The obtained epoxy-modified polymer is referred to as polymer E (epoxy equivalent of polymer 275).

<< Examples 1 to 4 and 7 and Comparative Examples 1 to 3 >>
1% by weight of each of the above epoxy-modified block copolymers was added to chlorinated paraffin having a chlorine content of 40% by weight, and the mixture was heat-treated at 160 ° C. for 5 hours while flowing nitrogen gas, and the amount of free hydrogen chloride (chlorinated paraffin And the amount relative to the total amount of heat stabilizer). The results obtained are shown in Table 1.

For comparison, when the heat stabilizer was not added (Comparative Example 1), 1 wt% of bisphenol type epoxy [trade name: Epicoat 828, manufactured by Shell Chemical Co., Ltd.] was used as the heat stabilizer. Case (Comparative Example 2) and 1% by weight
Table 1 also shows the results (Comparative Example 3) using the epoxidized soybean oil [trade name: ESBO, manufactured by Daicel Chemical Industries, Ltd.].

As is clear from the results shown in Table 1, the use of the heat stabilizer of the present invention can significantly reduce the amount of free hydrogen chloride.

<< Examples 5 and 6, Comparative Examples 4 and 5 >>
Polyvinyl chloride having the composition shown in Table 2 [trade name: G
The electrical characteristics (volume specific resistance) of the electric wire coating composition of Eon 103EP, manufactured by Nippon Zeon Co., Ltd.] were measured. The results are shown in Table 2. The epoxidized soybean oil and the epoxy-modified block copolymers A and E in Table 2 are the same as those used in Comparative Example 3, Example 4 and Example 7, respectively. As is clear from Table 2, the use of the heat stabilizer of the present invention improves the electrical properties of the polymer.

Table 1 Heat Stabilizer Amount of Free Hydrogen Chloride (wt%) Example 1 Epoxy Modified Block Copolymer A 0.018 2 〃 B 0.020 3 〃 C 0.017 4 〃 D 0.016 Comparative Example 1 None 0.3 2 Bisphenol Epoxy 0.085 3 Epoxidized soybean oil 0.070 Table 2 Comparative example 4 Comparative example 5 Example 5 Example 6 Polyvinyl chloride 100 100 100 100 Dioctyl phthalate 50 40 40 40 Epoxidized soybean oil-10--Modified block copolymer A-- 10 -〃 E---10 Calcium stearate 2.0 2.0 2.0 2.0 Zinc stearate 0.5 0.5 0.5 0.5 Stabilizing aid 0.5 0.5 0.5 0.5 Volume resistivity 1.2 × 10 ¹² 6.6 × 10 ¹¹ 4.5 × 10 ¹⁵ 6.0 × 10 ¹⁵ (Ω・ Cm) (Margins below)

Claims (1)

[Claims] 1. A conjugated diene compound of a block copolymer comprising a polymer block (A) mainly composed of a vinyl aromatic compound and a polymer block (B) mainly composed of a conjugated diene compound in the same molecule. A heat stabilizer for a halogen-containing polymer, which comprises an epoxy-modified block copolymer in which a double bond of an unsaturated carbon is epoxidized.