Synthesis of latexes with low concentration of volatile organic compounds (VOCs): effect of reduction techniques of VOCs on the properties of latexes and paints

摘要

The reduction of volatile organic compounds (VOCs) in the latexes produced by emulsion polymerization is a viable option, but it may compromise the performance of the latex in some situations. Different techniques for reduction of residual monomers and VOCs concentrations were studied for understanding the effect of these techniques and VOCs concentrations on the application properties of latexes and paints. Styrene/2-ethylhexyl acrylate latices functionalized with acrylic acid and acrylamide were produced by emulsion polymerization, followed by removal of residues and other VOCs with a chemical or physical technique, or with the combination of both. The effect of various parameters related to reduction techniques of VOCs, type of initiator, reducing agent and nitrogen stripping with steam were studied and correlated with the properties of latexes and paints. The combination of chemical and physical techniques was more effective for reducing the monomers and VOCs to latexes. The techniques employed for reduction of VOCs had a negative effect on the end-use properties of latex and paints. The abrasion resistance of the paint film was dependent on the technique employed and on VOCs concentration.