Method for preparing ethylene-propylene rubber-styrene-acrylonitrile terpolymer

Abstract

The invention provides a method for preparing an ethylene-propylene rubber-styrene-acrylonitrile terpolymer and belongs to the field of macromolecular chemistry. The method comprises the following steps of: adding an emulsifier consisting of disproportionated rosin and potassium hydroxide into normal hexane solution of ethylene propylene terpolymer, wherein the dosage of the emulsifier is 3.5 to 4.5 percent based on the mass of the normal hexane solution of ethylene propylene terpolymer, and the dosage of the potassium hydroxide is half the mass of the disproportionated rosin; stirring the mixed solution by a stirrer, wherein the stirring speed is 6,000 and 16,000rpm; and at the temperature of 60 and 70 DEG C, and under an action of an initiator and the protection of nitrogen gas, and adding styrene-acrylonitrile monomers for polymerization for 10 to 12 hours, wherein the mass ratio of the styrene monomers to the acrylonitrile monomers is 3:1, the initiator is potassium persulphate, the dosage of the potassium persulphate is 0.6 to 1.5 percent based on the mass of the monomers, and in the polymerization process, the dosage of the distilled water is 100 to 200 percent of the mass of the normal hexane solution of ethylene propylene terpolymer. The method has the advantages of simple emulsifying process, high grafting efficiency, low production cost and the realization of continuous production.

Description

technical field [0001] The invention belongs to the field of polymer chemistry, in particular to a method for preparing ethylene-propylene rubber grafts by emulsion polymerization. Background technique [0002] Styrene-EPDM-acrylonitrile copolymer AES is a new type of engineering plastic developed for the poor weather resistance of ABS. The commonly used ABS resin has excellent moldability, impact resistance and glossiness. However, since the butadiene rubber used in the synthesis of ABS contains a double bond structure, it is easily decomposed and oxidized by ultraviolet rays and heat. When used for a long time in places where weather resistance is required, physical properties may decrease and discoloration may occur. Although additives can be used to solve this problem, the stabilizer has limited effect on the long-term stability of the resin, so the most fundamental way is to use a stable rubber without a double bond structure. The resins manufactured by this method in...

AI Technical Summary

Problems solved by technology

The result of doing like this is: (1) in the obtained resin product, the content of rubber phase is relatively low, it is difficult to obtain the resin of high impact strength

(2) The particle size of the rubber phase is not easy to be effectively controlled, which is extremely unfavorable for adjusting the impact strength of the resin, achieving high gloss, and even obtaining a transparent resin

(3) It is not possible to use the process of directly blending graft powder and styrene / acrylonitrile copolymer resin like ABS, which will increase the production cost

(4) When switching between product grades of different impact strength grades, the amount of intermediate transition materials is relatively large, resulting in waste

The emulsification process of this patent is relatively complicated, and the addition of crosslinking agent divinylbenzene in the polymerization system makes the grafting efficiency low, which is not conducive to saving production costs