Controlled Synthesis of Thiazole-Based Polymers and Block Copolymers by RAFT Polymerization of Azolyl S-Vinyl Sulfides and Metal Complexation

Abstract

We studied the RAFT polymerization of five S-vinyl sulfide derivatives containing azole units, including 2-benzothiazolyl vinyl sulfide (BTVS), 2-thiazolyl vinyl sulfide (2-TVS), 1,3,4-thiadiazolyl vinyl sulfide (1,3,4-TVS), 5-methyl-1,3,4-thiadiazolyl vinyl sulfide (M-1,3,4-TVS), and 5-phenyl-1,3,4-oxadiazolyl vinyl sulfide (P-1,3,4-OVS). The polymerization of BTVS using dithiocarbamate-type and trithiocarbonate-type chain transfer agents (CTAs) was controlled, as shown by the relatively low polydispersities of the polymers and the linear increase in molecular weight with increasing conversion. In addition, the molecular weight could be controlled by adjusting the monomer-to-CTA ratio. The thiazole-, thiadiazole-, and oxadiazole-based polymers with relatively narrow molecular weight distributions and predetermined molecular weights were obtained by RAFT polymerization of all monomers using the dithiocarbamate-type CTA. The formation of metal complexes between the azole-containing polymers and various met...