Preparation and full characterization of cationic latex of styrene-butyl acrylate

Cationic latexes based on styrene and butyl acrylate using cetyl trimethyl ammonium bromide (CTAB) as surfactant were carried out using both batch and semicontinuous emulsion polymerization. Monomer conversion, particle size and its distribution, zeta potential, latex surface tension were determined as function of CTAB levels. Evolutions of these properties were followed, and the results from batch compared to those from semicontinuous process. It was revealed that polymerization rate in batch process was enhanced with CTAB, and the polymerization rate was controlled by addition rate of the preemulsion in semicontinuous process. Molecular adsorption area of CTAB on latex particle surface was calculated, which showed clearly that zeta potential and surface tension in the latex were directly related with surfactant adsorption on the particle surface. The molecular surface adsorption area of CTAB on latex particle could be used to explain the evolution of latex properties such as zeta potential and latex surface tension. (C) 2009 Elsevier Ltd. All rights reserved.