Kinetics and peculiarities of phase separation in the formation of semi‐interpenetrating polymer networks

The initial stages of phase separation in the formation of semi‐interpenetrating polymer networks (semi‐IPN's) based on copolymer from styrene with divinylbenzene (DVB)/poly(butyl methacrylate) (PBMA) were studied using an optical laser diffractometer. It was found that phase separation obeys the mechanism of spinodal decomposition. The peculiarity of phase separation in the system studied is due to the existence of a two‐stage process. Each stage exhibits different interdiffusion coefficients, sizes of microheterogeneity areas and activation energies.