Poly(vinyl acetate-co-butyl acrylate) latexes with N-methylol acrylamide were prepared by semi-continuous emulsion polymerization. The influence of the different initiators and various monomer ratios was studied to relate its physicochemical and colloidal properties. The changes in the copolymer latexes with the use of ammonium persulfate and potassium persulfate initiators were investigated by monitoring viscosity, molecular weights, molecular weight distribution and particle size. It was found that almost all physicochemical and colloidal properties of the latexes followed the same trends for both initiators. Potassium persulfate gave slightly higher results for number- and weight-average molecular weights than ammonium persulfate. Copyright (c) 2006 John Wiley & Sons, Ltd.