Colloidal Stability in Living Free Radical Miniemulsion Polymerization

摘要

The swelling of polymer particles during the early stages of living free radical miniemulsion polymerization was nvestigated. A new super-swelling state caused by the presence of a large number of oligomers was found. This super-swelling could be used to explain the instability issues reported. The effect of various factors on the super-swelling state was studied. It was found that super-swelling state is rather sensitive to recipe variations. Simply increasing the costabilizer level and/or using a nonionic polymeric surfactant would probably eliminate super-swelling, and hence, the instability.