JPS5911604B2 - Manufacturing method of new elastomer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a novel modified elastomer having a phenolic hydroxyl group in its side chain.

5-Generally, in order to use elastomers as final rubber products, an extremely complicated operation called vulcanization is required, and it is well known that there are limits to their use and workability.

In order to avoid the complicated operations and difficulties associated with vulcanization, it is effective to impart reactivity to the elastomeric polymer itself. That is, the difficulties associated with the vulcanization operation of conventionally produced elastomeric polymers can be greatly reduced by providing the elastomeric polymer itself with specific reactive groups. Furthermore, as a 15-reactive polymer,
It can be used for various purposes utilizing its reactivity. The present inventors first added a phenolic monomer having a specific structure during the production of polybutadiene or styrene-butadiene rubber and copolymerized it20, thereby obtaining a modified elastomer having phenolic hydroxyl groups in the side chain. However, as a result of intensive research aimed at developing elastomeric polymers that retain the properties of elastomeric polymer compounds and have reactivity in the polymer itself, we found that 25 cations and cations with specific structures The inventors have discovered that a novel modified elastomer can be obtained by graft polymerizing a radically polymerizable phenol compound onto an elastomer, leading to the completion of the present invention.

30 That is, the present invention uses a general inner layer (
Here, R represents an alkyl group or hydrogen, R1 to R5 represent an alkyl group, hydrogen or a hydroxyl group, and any one of R1 to R5 represents a hydroxyl group.

Note that the above hydroxyl group may be protected with an alkyl group, an acyl group, or the like. The present invention provides a method for producing an elastomer having a phenolic hydroxyl group in a side chain, which comprises graft copolymerizing a phenolic monomer represented by the following formula.

The phenolic monomers having a specific structure used in the method of the present invention are the cationic and radically polymerizable phenolic monomers described above.

Specific examples include m-hydroxystyrene, p-
-Hydroxystyrene, m-hydroxy-α-methylstyrene, 4-hydroxy-3-methylstyrene, 4-hydroxy-3,5-dimethylstyrene, 4-hydroxy-3,5-diisopropylstyrene, 4-hydroxy-
Examples include, but are not limited to, compounds such as 3-tert-butylstyrene, 4-hydroxy-3,5-di-tert-butylstyrene, and 4-hydroxy-3-methyl-α-methylstyrene. do not have. These phenolic compounds can be used alone or in combination of two or more.
In addition, these phenolic compounds may be protected with an alkyl group, acyl digroup, etc., if necessary. In the case of elastomers normally produced by anionic polymerization, it is necessary to increase the amount of polymerization initiator in order to copolymerize the compound represented by general manager (4), so the elastomer and the compound track (4) are graft copolymerized. This is desirable.

Combination in this case? The amount of (trans) added is elastomer 100
Select 0.5 to 10 parts by weight. Examples of the elastomer include solution-polymerized styrene-butadiene rubber, cis-polybutadiene rubber, and polyisoprene rubber, which are usually produced using an anionic or coordinating anionic polymerization initiator such as a Ziegler type 1 catalyst or an alkyllithium catalyst.

It goes without saying that elastomers produced using cationic or radical polymerization initiators, such as polybutadiene rubber, styrene-butadiene rubber, high styrene rubber, acrylonitrile-butadiene rubber, butyl rubber, and chloroprene rubber, are also included. Graft polymerization is carried out at 0 to 300°C in the presence or absence of a polymerization initiator.
Preferably, the polymerization can be carried out at a temperature of 40 to 200° C. by emulsion polymerization, solution polymerization, bulk polymerization, suspension polymerization, or the like.

When using a polymerization initiator, a radical polymerization initiator is preferable, such as potassium persulfate, cumene hydroperoxide, peracetic acid, tert-butylperoxytriphenyl acetate, benzoyl peroxide, 2,2'
-Azobisisobutyronitrile and the like can be used.

As the emulsifier used in the emulsion polymerization method, nonionic, anionic, cationic, or amphoteric surfactants can be used. In addition, the solvent used in the solution polymerization method is to dissolve the elastomer and monomer,
In addition, inert solvents that do not react with these solvents, such as benzene, toluene, n-hexane, tetrahydrofuran, methyl chloride, and cyclohexane, can be used. The polymerization time varies depending on the formulation, but generally 48 hours or less is sufficient. The modified elastomer thus obtained not only has excellent crosslinking properties as a polymer compound having a phenolic hydroxyl group in the side chain while retaining the physical properties of an elastomer, but also has excellent thermal stability, tackiness, and adhesive properties. It has good compatibility with polymers into which phenol nuclei have been introduced, and can be used extremely effectively, especially in the form of latex, for textiles, paints, coatings, and impregnating agents. Next, aspects of the present invention will be explained using Examples, but the present invention is not limited to these Examples unless the gist thereof is exceeded.

Example 1 Graft copolymerization of polybutadiene and m-/p-hydroxy-α-methylstyrene (mixture of m-integrated and p-integrated) was carried out according to the following recipe using a stirring type glass container having an internal volume of 1 ton.

JSRO7OO, trade name of Japan Synthetic Rubber Co., Ltd. After polymerization was carried out at a temperature of 65 to 85° C. for 6 hours under a nitrogen stream, methanol was added as a terminator to terminate the polymerization.

Magnesium sulfate was added to the resulting emulsion to salt out the polymer, which was washed with water and then dried. The yield of the elastomeric polymer thus obtained was 104 parts by weight. 10 tons of the obtained polymer was extracted with acetone using a Soxle extractor and separated into an acetone soluble part and an insoluble part.
- A homopolymer of methylstyrene was isolated. Evaporate the acetone to dry the acetone soluble part and reduce the solid content to 0.1
Got 2y. As a result, the grafting efficiency of m-/p-hydroxy-α-methylstyrene is about 55%. Example 2 100 parts by weight of cis-polybutadiene (Diene NF35, trade name of Asahi Kasei Co., Ltd.) was dissolved in 1000 parts by weight of toluene in a stirred glass container with an internal volume of 2 tons that was purged with nitrogen.
The mixture was heated to 65°C and thoroughly stirred.

Next, 1.2 parts by weight of lauryl peroxide (a dilute solution of toluene) as a polymerization catalyst was added to the reactor, and the temperature was maintained at 65° C. and vigorously stirred to mix thoroughly with the raw materials. Here, 4 parts by weight of 4-hydroxy-3,5-di-tert-butylstyrene (a dilute solution of toluene) was put into the dropping load and gradually added dropwise at 65°C, and in about 1 hour, 4-hydroxy-3,5-butylstyrene was added. - The dropping of di-tertiary-butylstyrene was completed.

Claims (1)

[Scope of Claims] 1. 100 parts by weight of an elastomer obtained by polymerizing a conjugated diene or a mixture of a conjugated diene containing a conjugated diene as a main component and a monoethylenically unsaturated monomer and the general formula (A
)▲There are mathematical formulas, chemical formulas, tables, etc.▼ (Here, R_ represents an alkyl group or a hydrogen atom, and R_
1 to R_5 represent an alkyl group, a hydrogen atom, or a hydroxyl group, and any one of R_1 to R_5 represents a hydroxyl group. Note that the above hydroxyl group may be protected with an alkyl group, an acyl group, or the like. ) phenolic monomer represented by 0.
A method for producing an elastomer having a phenolic hydroxyl group in a side chain, the method comprising graft copolymerizing 5 to 10 parts by weight.