Styrenebutyl acrylate mini-emulsion-based pressure sensitive adhesives

Abstract

Adhesives are defined as substances capable of holding at least two surfaces together. A class of adhesives called pressure-sensitive adhesives (or PSAs) is characterized by instantaneous adhesion upon application of light pressure. In order to develop new application-specific products and improve existing processes, there is a need to identify the factors that influence the performance of PSAs. Operating conditions like feed composition, temperature, and solid content will affect latex properties such as copolymer composition, molecular weight distribution (MWD) and particle size distribution (PSD). Those latex properties can in turn affect the performance of the adhesive. Because of environmental concerns and government regulations to substitute solvent-based systems by water-borne products, there is a growing interest in producing such PSAs by emulsion (or mini-emulsion) polymerization. Mini-emulsions allow for improved control over the PSD compared to conventional emulsion polymerizations. Coupled with control over the MWD and copolymer composition, mini-emulsions could offer the possibility of tailoring the desired properties of PSAs. It was of interest in this thesis, to measure the effect of varying particle size and copolymer composition on adhesive properties. Based on this primary objective, a series of styrene/butyl acrylate mini-emulsion copolymerizations were carried out in a 1.2L stainless steel reactor. (Abstract shortened by UMI.)