Control of free-radical polymerization of 2,2,2-trifluoroethyl methacrylate (TEMA) by a substituted fluorinated tetraphenylethane-type INITER

This paper deals with the free radical polymerization of 2,2,2-trifluoroethyl methacrylate (TEMA) initiated by a substituted fluorinated tetraphenylethane-type INITER. nthesis of a new fluorinated substituted tetraphenylethane is described. This initiator, prepared from benzophenone and 3,3,3-(trifluoropropyl)chlorodimethylsilane behaves as an INITER when used to polymerize TEMA. In the first period of polymerization, telechelic oligomers are formed. They were isolated from the mixture and their structure was characterized by 1H-NMR spectroscopy. By thermal cleavage at the bonds between the last monomer unit and the end groups from the initiator, these telechelic oligomers are effective initiators of further free-radical polymerization of ethylenic monomers, yielding block copolymers besides the respective homopolymer. Thus, in a second step, styrene was introduced into poly(TEMA) to produce block copolymers with a macroinitiator efficiency close to 85%.