Controlled Copolymerization of 1‑Octene and (Meth)acrylates via Organotellurium-Mediated Living Radical Polymerization (TERP)

Abstract

Copolymerization of 1-octene and (meth)­acrylates, such as methyl acrylate, trifluoroethyl acrylate (TFEA), methyl methacrylate, and trifluoroethyl methacrylate, under organotellurium-mediated living radical polymerization (TERP) conditions was investigated. Polymerization under thermal conditions gave copolymers with considerably broad molecular distributions (polydispersity index [PDI] > 1.45), whereas that under photoirradiation greatly increased the PDI control. Structurally well-controlled copolymers with number-average molecular weights (<i>M</i>_n) of 3000–18 000 and low PDIs (1.22–1.45) were obtained. Addition of Brønsted acids, such as 1,3-C₆H₄[C­(CF₃)₂OH]₂ and hexafluoroisopropanol, increased the insertion of 1-octene into the copolymer. The molar fraction of 1-octene (MF_oct) reached ∼0.5 in the copolymerization using TFEA as an acrylate monomer and excess amount of 1-octene in the presence of the acid. The copolymer was used as a macro-chain-transfer agent for the synthesis of block copolymers. This is the first example of the use of this type of copolymer as a macro-chain-transfer agent in the controlled synthesis of block copolymers