JPH0713122B2 - Method for producing methyl methacrylate butadiene styrene copolymer resin - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a methyl methacrylate butadiene styrene copolymer resin having excellent processability and impact resistance at low temperatures.

[Conventional technology]

Vinyl chloride resin is widely used in various fields due to its advantages such as chemical resistance, oil resistance, flame resistance, high rigidity, low cost and wide application, but it has poor workability and impact resistance. Since it is inferior and has a problem of poor physical properties at low temperature, its use is also limited in various ways, and the characteristics of the vinyl chloride resin cannot be sufficiently exhibited.

In order to improve the processability and impact resistance of this vinyl chloride resin, PVC vendors are positively co-polymerizing or graft-copolymerizing or mixing the vinyl chloride resin with various compound components, and
Methods have been proposed to try to improve the quality of C resin.

[Problems to be Solved by the Invention]

Among these, it is generally accepted that methyl methacrylate styrene styrene (abbreviated as MBS) resin has the effect of improving processability and impact resistance with respect to vinyl chloride resin, but in reality, it does not affect the transparency of the product resin. There are problems such as bad influences and low effect of improving physical properties at low temperatures.

As a method for producing an MBS resin, a latex (emulsion) having rubber properties, for example, butadiene or a copolymer thereof is generally used as a substrate, and this is used as a monomer for various aromatic vinyl compounds or acrylic acid ester compounds. MBS resin is obtained by carrying out multiple-order copolymerization reactions. However, the MBS resin obtained by this method has a substantial improvement effect on the PVC resin in terms of modification, impact resistance, and processability, but it does not show any significant improvement effect on the characteristics at low temperatures, and the resin Since there is a problem that adversely affects the transparency of, the product processed and molded by this resin is difficult to withstand impact, impact and drop at low temperature, and easily bursts,
It had a great influence on the practical use of the product.

[Means for Solving the Problems]

As a result of intensive studies to solve the above-mentioned problems, the present inventors have used a butadiene-based compound as a substrate, and have used this as a multi-order copolymerization with an aromatic vinyl compound monomer and / or an acrylic acid ester-based compound monomer. It was found that an MBS resin having significantly improved physical properties and transparency, particularly at low temperature, can be obtained by copolymerizing a vinyl ether monomer that occupies 0.5 to 10% by weight of the above mixture while performing the above. The invention has been reached.

That is, according to the present invention, a butadiene-based copolymer latex is mixed with a monomer copolymerizable with the latex, and a multi-order copolymerization reaction in the presence of a polymerization initiator and an emulsifier is performed. A method for obtaining a methyl methacrylate butadiene styrene copolymer resin composition having a good effect of modifying impact resistance, processability, and impact resistance at low temperature by further causing a copolymerization reaction with a vinyl ether monomer accounting for wt% Is.

The rubber-like latex used in the present invention may be a rubber-like latex used in general MBS polymerization such as butadiene latex or butadiene styrene latex. The amount of latex used is 30 to 70% by weight of the total resin, preferably 40 to 65% by weight.

Further, the monomer used in the multi-order copolymerization of the present invention,
It is selected from aromatic vinyl compounds such as styrene, α-methylstyrene and paramethylstyrene, and alkyl methyl acrylate compounds such as methyl methacrylate, ethyl methyl acrylate, methyl acrylate, ethyl acrylate and butyl acrylate. At least one
Alternatively, it is a compound formed by mixing two or more kinds, and the amount thereof is 30 to 70% by weight, preferably 35 to 60% by weight, based on the whole resin.

The vinyl ether monomer used in the present invention is represented by the following general formula.

However, in the formula, R = −CxHy, in which x = 1 to 16, y = 2x +
It is 1.

For _{example, CH 2 = CH-OCH 3} , CH 2 = CH-OC 2 H 5, CH 2 = CH-O (CH 2) 3 CH 3, CH 2 = CH-OC 10 H 21, CH 2 = CH-OC ₁₂ H ₂₅ , CH ₂ ═CH—OC ₁₆ H ₃₃ , and the like, and one or two or more of these are selected and used alone or in combination. The amount used is 0.
It is 5 to 10% by weight, particularly preferably 1 to 5% by weight. If it is less than 0.5% by weight, the effect of improving the strength at low temperature is not exerted, and if it exceeds 10% by weight, the impact resistance is adversely affected.

The emulsifier applied to the present invention may be any emulsifier generally used in the production of synthetic rubber. These include, for example, sodium oleate, sodium stearate, sodium fatty acid and the like. The amount used is 0-10% by weight of the total resin. In order to control the appropriate growth of particles in the copolymerization reaction process of the above compound, the type of the polymerization initiator is usually selected and used, and the amount thereof is appropriately adjusted. Alternatively, at the time of copolymerization, an electrolyte, an inorganic salt or an organic salt is used, and a crosslinking agent is used if necessary to control the particle size.

The polymerization initiator used in the present invention is not particularly limited,
Any oil-based or water-soluble initiator generally used for suspension combination, emulsion polymerization, solution polymerization, block polymerization can be used. These are selected from organic peroxides such as cumene hydroperoxide, diisopropylbenzene hydroperoxide, p-methane hydroperoxide and tetramethylbutyl hydroperoxide, or inorganic initiators such as persulfates and perborates. These are used alone or in admixture of two or more, and the amount used is 0.01 to 5% by weight of the total resin.

The electrolyte, organic salt or inorganic salt used in the present invention includes, for example, sodium formaldehyde sulfoxylate, sodium sulfate (Na ₂ SO ₁ ), iron sulfate (FeSO ₄ ), etc. It is 5% by weight.

The target of the resin for modification using the resin of the present invention is PV
Not limited only to C resin, vinyl acetate copolymerizable with vinyl chloride or graft copolymerizable with vinyl chloride, ethylene, etc., having a vinyl chloride component content of 70% or more in its molecule, Further, it is more preferable if it has the characteristics of a vinyl chloride resin. The resin composition obtained by the present invention can also be used as a mixture with other appropriate polymer.

〔Example〕

 The present invention will be described below with reference to examples and comparative examples.

Example 1 A reactor equipped with a stirrer was charged with the following.

Butadiene styrene Latex 48 parts Sodium oleate 2 parts Sodium formaldehyde sulfoxyate 2 parts Cumyl hydroperoxide 1 part Isobutyl vinyl ether 5 parts Deionized water 200 parts Then, heat up to 60 ° C while stirring in a nitrogen vapor stream, After maintaining the temperature and reacting for about 1 hour, 2
Within 25 hours, 25 parts of styrene and 0.2 parts of cumyl hydroperoxide as an initiator were continuously charged, and the above reaction product was continuously reacted. After the conversion reached 48%, the reaction was continued for another 2 hours. Within 22 parts by weight of methyl methacrylate and 0.2 part of cumyl hydroperoxide as an initiator were added to carry out a multi-order copolymerization to reach an addition rate of 99.2%,
The MBS latex thus obtained was condensed, washed with water and dried to obtain a powdery MBS multiple graft copolymer.

Example 2 The components and parts by weight of the reactants used were 5 parts isobutyl vinyl ether and 22 parts methyl methacrylate in the above examples, whereas in this example 3 parts for the former and 25 parts for the latter. Example 1 except for using
The same apparatus and method used in Example 1 were used to obtain an MBS multiple graft copolymer.

Example 3 5 parts of cetyl vinyl ether were used instead of isobutyl vinyl ether, the other apparatus, method and reactant components and parts used were the same as in example 1, whereby
An MBS multiple graft copolymer was obtained.

Example 4 5 parts of cetyl vinyl ether used, styrene
Twenty-five parts were continuously added to the reaction within 2 hours. The apparatus, method and other components and the number of parts of the reaction product used were the same as in Example 3, whereby an MBS multiple graft copolymer was obtained.

Example 5 The cetyl vinyl ether used was 5 parts, which was continuously added to the reaction product together with 22 parts of methyl methacrylate in 2 hours, the other apparatus, method and reaction product used were the same as in Example 3. Thus, an MBS multiple graft copolymer was obtained.

Comparative Example 1 In Example 1, the isobutyl vinyl ether was not used, the amounts of styrene and methyl methacrylate were changed to 28 parts and 24 parts, respectively, and the other apparatus, method and reactant used were the same as in Example 1. Thus, an MBS multiple graft copolymer was obtained.

(Test) The MBS copolymer resin obtained in each of the above examples was molded into a test piece with the following formulation, and its physical properties were measured.

(1) Combination prescription PVC (= 800) 100 parts MBS 10 parts Octyl / tin mercaptide 1.6 parts Partial fatty acid ester of glycerine 0.6 part Modified complex ester wax Polymethyl methacrylate (PMMA) 1.0 part (2) Roll kneading (6 inches) 180 ° C x 5 minutes Press: After preheating at 175 ° C x 2.5 minutes, pressure 80kg / cm ²
Pressing was carried out at 70 ° C for 1 minute.

The following table shows the effect of modifying the physical properties of the PVC resin by the MBS resins prepared in Examples 1 to 5 and Comparative Example 1.

* Explanation of test method (1) Glossiness Test piece 5.08cm × 12.7cm × 0.5tm / m 3 pieces each for gloss meter (KOGYO
CO, Ltd. VG-IC type) was used to measure the glossiness of the test pieces on both the roll contact surface (△) and the non-contact surface (*), and the average value was read.

(2) Transparency (Transmittance) Test piece 35m / m × 12.7m / m × 3m / m 3 pieces each with a transmissometer (wavelength 51
(0 nm) in the range of 0 to 100%.

(3) Cold resistance Test pieces 5.08 cm × 20.32 cm × 0.5 tm / m 20 pieces each were left at a low temperature of -25 ° C for 15 minutes, and then the number of ruptures was tested by bending impact of 2 kg × 90 ° angle. went.

(4) Whitening The test piece was bent by a bending method, the bent portion was compared with the standard piece, and the degree of whitening was visually determined.

〔The invention's effect〕

The MBS copolymer resin composition obtained by the present invention is superior in impact resistance at low temperature, processability and transparency to the MBS resin produced by the conventional method, has wide applications, and has improved product quality and value. It is a resin composition.

Claims (6)

[Claims] 1. A butadiene-based copolymer latex and a monomer of an aromatic vinyl compound or an alkyl acrylate compound which can be copolymerized therewith are respectively subjected to a multi-order copolymerization reaction in the presence of a polymerization initiator. A method for producing a methyl methacrylate butadiene styrene copolymer resin, which comprises copolymerizing by adding a vinyl ether monomer during the curing process. 2. The methyl methacrylate butadiene styrene copolymer resin according to claim 1, wherein the butadiene copolymer latex is one kind selected from butadiene latex and butadiene styrene copolymer latex, or a mixture thereof. Manufacturing method. 3. A method for producing a methyl methacrylate butadiene styrene copolymer resin according to claim 1, wherein the aromatic vinyl compound is one kind or various kinds selected from the group consisting of styrene, α-methylstyrene and paramethylstyrene. Method. 4. The alkyl acrylate compound is selected from the group consisting of methyl methacrylate, ethyl methyl acrylate, methyl acrylate, ethyl acrylate, butyl acrylate and the like, or a mixture of two or more thereof. A method for producing the methyl butadiene styrene styrene copolymer resin according to claim 1. 5. The method for producing a methyl methacrylic acid butadiene styrene copolymer resin according to claim 1, wherein the vinyl ether monomer is represented by the following general formula. [Wherein, R is -CxHy, x is an integer of 1 to 16,
y = 2x + 1]. 6. The vinyl ether monomer is added to the copolymerization reaction mixture once or several times or continuously at the initial, midway or end of the copolymerization reaction, and the addition amount of the whole resin is The method for producing the methyl methacrylate butadiene styrene copolymer resin according to claim 1, which is 0.5 to 10% by weight.