CONTROL OF NETWORK STRUCTURE IN FREE-RADICAL CROSS-LINKING COPOLYMERIZATION

A kinetic model which describes the network structure development during free-radical crosslinking copolymerization is proposed. The model was successfully applied to various batch copolymerization systems such as methyl methacrylate/ethylene glycol dimethacrylate, styrene/p-divinylbenzene, styrene/ethylene glycol dimethacrylate, and acrylamide/N,N'-methylene-bis-acrylamide. The model calculations suggest that polymer networks synthesized by free-radical copolymerization are, in general, inhomogeneous at least on a microscopic scale. This model can be used to control the network structure, and a semi-batch policy to produce homogeneous polymer networks is proposed.