SYNTHESIS OF A SPECIAL STRUCTURAL VINYL ACETATE-ETHYLENE-BUTYL ACRYLATE LATEX

摘要

EVA latex is one of the popular used latices. The content of ethylene of ordinary EVA latex is about 15%, which was obtained by emulsion polymerization at mediate pressure (about 4MPa). Three methods for producing EVA latex with high ethylene (E) content and long sequence ethylene-ethylene structure were presented. The first method is direct emulsion polymerization at high-pressure (about 20Mpa) which is difficult to carry out in industry. In the second method, ordinary EVA resin is dissolved in an organic solvent to form a polymer solution, then which is added to water containing emulsifier at high-speed stirring to obtain stable emulsion, and then the solvent is evaporated. The third method is direct emulsification method. EVA resin is direct emulsified at high temperature and high-pressure with high-speed stirring. In this paper, EV A resin (the content of ethylene was 60% and there are long ethylene-ethylene units.) was dissolved in a monomer mixture of vinyl acetate and acrylate. Then the above polymer-monomer solution was added at high speed stirring to a reactor containing water and emulsifying agent to obtain a emulsion, and then adding initiator in it to carry out emulsion polymerization at ordinary speed stirring. A latex with core-shell structure was obtained. There are long sequence ethylene-ethylene units in the latex, and the latex has very good water-resistance.