title: Cationic RAFT polymerization using ppm concentrations of organic acid.
abstract: A metal-free, cationic, reversible addition-fragmentation chain-transfer (RAFT) polymerization was proposed and realized. A series of thiocarbonylthio compounds were used in the presence of a small amount of triflic acid for isobutyl vinyl ether to give polymers with controlled molecular weight of up to 1×10(5) and narrow molecular-weight distributions (Mw /Mn <1.1). This "living" or controlled cationic polymerization is applicable to various electron-rich monomers including vinyl ethers, p-methoxystyrene, and even p-hydroxystyrene that possesses an unprotected phenol group. A transformation from cationic to radical RAFT polymerization enables the synthesis of block copolymers between cationically and radically polymerizable monomers, such as vinyl ether and vinyl acetate or methyl acrylate.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan).
authors.forename: Mineto
authors.initials: M
authors.lastname: Uchiyama
authors.forename: Kotaro
authors.initials: K
authors.lastname: Satoh
authors.forename: Masami
authors.initials: M
authors.lastname: Kamigaito
keywords: RAFT polymerization; block copolymers; cationic polymerization; living polymerization; organocatalysis