The effect of maleic acid diesters type on the stability of vinyl acetate emulsion polymers

Abstract

Vinyl acetate (VAc) was copolymerized with two different maleic acid diesters, dibutyl maleate (DBM) and dioctyl maleate (DOM) at different comonomer ratios by semi-continuous emulsion polymerization method. The effects of maleic acid diesters type and amount on the latex properties of VAc emulsion polymers were investigated. The particle size, viscosity, zeta potential, surface tension and conductivity of the latexes were determined by Dynamic Light Scattering (DLS), Brookfield viscometer, zeta potential analyzer, Du Nouy tensiometer and electrical conductometer, respectively. The latex freeze-thaw stability and ionic strength resistance were also analyzed. The experimental results have shown that the variety in comonomer type and amount created significant differences on the latex properties of VAc emulsion polymers. With the use of DBM or DOM in a certain amount, the particle size and particle size distribution of VAc emulsion polymers were decreased while their latex stability were increased. DBM was also more effective in improving the latex stability than DOM. Consequently, it was clearly observed that these two comonomers enhanced the overall latex properties of VAc homopolymer depending on their type and amount. (C) 2016 Elsevier B.V. All rights reserved.