Characterization of randomly branched polymers formed by end-linking linear polystyrene using controlled free radical polymerization

Randomly branched polystyrene (PS) was synthesized by end-linking monodispe rse linear PS chains with divinylbenzene using controlled free radical poly merization. samples obtained at different reaction extents were characteriz ed using size exclusion chromatography and static and dynamic light scatter ing. The results are compared with those obtained on randomly branched poly (methyl methacrylate) (PMMA). The overal structure of branched PS was found to be the same as that of branched PMMA despite the very different local s tructure. The results strongly support the idea that the formation of polym eric gels is a universal process that may be described by the percolation m odel.