Block copolymers of styrene and 4-vinylpyridine: Synthesis and structure

It is shown that the block copolymerization of styrene and 4-vinylpyridine mediated by the nitroxide TEMPO occurs via the pseudoliving radical mechanism during initiation by both of the adducts poly(4-vinylpyridine)-TEMPO and polystyrene-TEMPO. For both systems, the Mn values of the polymers linearly increase with monomer conversion. Optimum conditions of the controlled synthesis of block and block random copolymers are found, and the samples with regularly variable lengths and types of blocks are obtained. As evidenced by electron-microscopic studies, the polymers are capable of self-organization in the block and thin films accompanied by the formation of nanostructures, whose morphology may be controlled through variation in the composition and type of blocks. In this case, the sizes of domains vary from 20 to 60 nm.