Controlled Polymerization of N‐Vinyl Imidazole, N‐Vinyl Pyrrolidone, and N‐Vinyl Carbazole with Dithiocarbamates toward High Molar Mass Polymers

Abstract

Achieving control over the polymerization of less activated monomers (LAMs) like N‐vinyl carbazole (NVC), N‐vinyl pyrrolidone (NVP), and N‐vinyl imidazole (NVIm) to produce high molar mass polymers posing a significant challenge. To accomplish this, we synthesized eight different dithiocarbamates based RAFT (reversible addition‐fragmentation chain transfer) agents and employed them to polymerize NVIm, NVC and NVP in order to understand and establish a suitable agent for their controlled polymerization to achieve high molar mass polymers. Chain ends presence of these RAFT‐derived polymers was established through 1H NMR studies. Further, these active chain ends are used for chain extension reactions to prepare block copolymers. Synthesized RAFT agents 04, 05, 06, and 08 that are bearing primary leaving groups (methyl 2‐acetate, ethyl 2‐acetate, tert‐butyl 2‐acetate and cyanomethane) displayed moderate to good control over the polymerization of NVIm and NVC. Among these, RAFT agent‐08 with cyanomethane leaving group produced poly(NVIm) and poly(NVC) with the highest molar masses of 44,670 Da (1.52) and 53,620 Da (1.4) respectively. Interestingly, RAFT agents bearing both secondary and primary leaving groups showed good control over the NVP polymerization. Notably, RAFT agent‐02 with ethyl‐2‐propionate leaving group yielded poly(NVP) with the highest molar mass of 89,450 Da and dispersity of 1.43.This article is protected by copyright. All rights reserved