| Summary: | Hyperbranched polymers have emerged as a new class of macromolecules that show architectural beauty and multifaceted functionality of d- drimers while enjoying the ease of being prepared by simple, sing- step reaction procedures. A number of strategies have been developed for the synthesis of hyperbranched polymers. The commonly adopted - proach is self-condensation polymerization of AB -type monomers with x x?2 where A and B are mutually reactive functional groups, dating back to the theoretical work of Flory in the early 1950s [1]. Because of the limited commercial availability and dif?cult synthetic access to multifu- tional monomers bearing multiple, mutually reactive groups, alternative approaches suchas copolymerizations ofA monomers with B comonomers 2 x (x?3) have been developed [2{u2013}7]. Other polymerization reactions including self-condensing vinyl polymerizations initiated by cationic [8] and radical catalysts [9,10] and ring-opening multibranching polymerizations [11{u2013}15] have been explored, mainly for the synthesis of non-conjugated hyp- branched polymers [16{u2013}18]. Hyperbranched macromolecules have been constructed from various functional groups, among which, carbon-carbon triple-bond functionality uniquely stands out because it offers ready access to hyperbranched conju- tive macromolecules. Being unsaturated, it accommodates various addition reactions. In comparison to vinyl and alkyl protons, the acetylenic proton is most acidic (pK = 26; cf., pK =45forethyleneandpK = 62 for ethane), a a a thus enabling facile substitution and coupling reactions.
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