Living linking chemistry: A novel route to star-branched and hetero-arm star-branched polymers

The reactions of living polymer chains with non-terminating linking reagents such that the living character of the active centers are not destroyed are defined as a living linking reactions. Thus the reaction of two moles poly(styryl)lithium, (I), in benzene with one mole of the difunctional living linking reagent meta-bis(1-phenylvinyl)benzene, (II), yields one mole of a difunctional living polymer, (III). Living four arm star polymer, (IV), was prepared by the addition of additional styrene monomer to (III) at 0-4{dollar}spcirc{dollar}C. Four arm star polymers were characterized by size exclusion chromatography using a low angle laser light scattering detector. Comb-branched polymer was prepared by linking (IV) with an additional equivalent of (II). Heteroarm star polymer was prepared by the addition of isoprene to (III). Two new trifunctional linking reagents have been prepared 3,3{dollar}spprime{dollar}-Bis(1,1{dollar}spprime{dollar}-phenylvinyl)-1,1-diphenylethylene, (V), and 1,3,5-Tris(1-phenylethylenyl)-benzene, (VI). Six arm star branched polystyrene was prepared from (VI).