Syndioselective coordination (Co)polymerization of triphenylamine-substituted styrenes via a scandium catalyst system

Coordination polymerization of the triphenylamine-substituted styrene derivatives N,N-diphenyl-4′-vinyl-[1,1′-biphenyl]-4-amine (FSt1) and N,N-bis(4-bromophenyl)-4′-vinyl-[1,1′-biphenyl]-4-amine (FSt2) was successfully achieved via the rare-earth metal catalyst (C5Me4SiMe3)Sc-(CH2SiMe3)2(THF). The catalyst system showed high activity and excellent syndioselectivity (rrrrå 99%) for the polymerization of FSt. Moreover, the syndioselective copolymerization of FSt with styrene was also achieved with this catalyst system. The insertion rate of triphenylamine-substituted monomers could be tuned by simply changing the feed amount. Strikingly, the copolymers showed random or gradient sequence distributions depending on the different reactivity ratios of FSt with St. Representative photophysical properties, such as those observed using UV–vis absorption and fluorescence spectroscopy, of the (co)polymers were also characterized.