Surface characterization of styrene/acrylamide copolymer latex particles

摘要

AbstractSurface characteristics of styrene/acrylamide copolymer latex particles prepared without emulsifier were investigated as a function of acrylamide fraction in charged monomers. The presence of swelling or water‐soluble polymer layer at the particle surface was suggested, and its thickness increased with increasing acrylamide fraction. The surface charge densities by conductometric and potentiometric titrations wer about half that of polystyrene latex particles at low pH and they increased slightly with increasing pH. Regarding the heterocoagulation between styrene/acrylamide copolymer latex particles and polystyrene latex particles, the critical coagulation concentration of KCI decreased with increasing acrylamide fraction. The consideration in terms of the interaction due to electrostatic and van der Waals forces also suggested that the swelling or water‐soluble polymer layer at the particle surface plays an important r