Synthesis of multicompartment nanoparticles of a triblock terpolymer by seeded RAFT polymerization

Abstract

Seeded RAFT polymerization is proposed to prepare multicompartment nanoparticles of the poly(N,N-dimethylacrylamide)-b-polystyrene-b-poly(4-vinylpyridine) (PDMA-b-PS-b-P4VP) triblock terpolymer, which contain a polystyrene (PS) core, discrete poly(4-vinylpyridine) (P4VP) microphases on the PS core, and a solvated poly(N,N-dimethylacrylamide) (PDMA) corona. Following this seeded RAFT polymerization, the seed nanoparticles of poly(N,N-dimethylacrylamide)-b-polystyrene are initially prepared through dispersion RAFT polymerization, and then the P4VP block is introduced onto the seed nanoparticles by seeded RAFT polymerization to prepare the corona–core nanoparticles of PDMA-b-PS-b-P4VP containing a PS core and a mixed corona of P4VP and PDMA. When the corona–core nanoparticles of PDMA-b-PS-b-P4VP are dispersed in water, the P4VP chains, which are segregated by the neighboring PDMA chains, deposit on the PS core to form the discrete P4VP microphases on the PS core, and they convert into multicompartment nanoparticles. It is found that the size of the P4VP microphases on the PS core increases with the polymerization degree of the P4VP block. This seeded RAFT polymerization is believed to be a valid method to prepare block copolymer multicompartment nanoparticles.