An investigation of the emulsion terpolymerization of 2-ethylhexylacrylate–vinyl acetate–acrylic acid

Abstract

An investigation of the emulsion polymerization of 2-ethylhexylacrylate (EHA)—vinyl acetate (VAc)—acrylic acid (AA) has been done. It was found that the polymerization rate depends on the AA level and that particle nucleation occurs throughout the entire conversion range. At the 5% AA level, there is significant coagulation. The number of particles depends on the balance between nucleation and coagulation. Addition of a small amount of water-soluble comonomer has no significant effect on the course of polymerization, but the viscosity of the latex can increase significantly. The dependence of latex viscosity on pH on neutralization has been studied. The maximum viscosity reached on neutralization depends on the acrylic acid level and the semibatch policy used in the latex synthesis. Addition of salt is a simple and effective way to control viscosity buildup during neutralization.