Electrostatically and electrosterically stabilized latices of acrylic copolymers used as pressure-sensitive adhesives

Electrostatically and electrosterically stabilized emulsion copolymers based on poly(butyl acrylate-co-vinyl acetate-co-acrylic acid) and poly(2-ethylhexyl acrylate-co-vinyl acetate-co-acrylic acid) were prepared by semicontinuous emulsion polymerization in order to obtain pressure-sensitive adhesives. The prepared dispersions were characterized by their concentration, intrinsic viscosity, rheological behavior, glass transition temperature, and adhesive performances on the standard test panel, i.e. stainless steel. The surfactants have a great influence on latices viscosities, which become smaller when the content of nonionic surfactant increases, and affect also the shear and peel strength of the final adhesives. The viscosity and rheological behavior are also influenced by the presence of 2-ethylhexyl acrylate instead of butyl acrylate.