Synthesis and characterization of branched bisphenol-A polycarbonates functionalized with siloxane

Branched and grafted silicone polycarbonates were synthesized from branched allyl polycarbonate (Br-Allyl-PC) precursors and siloxanes by a controlled hydrosilylation reaction using Karstedt’s catalyst. The Br-Allyl-PCs were synthesized using a bisphenol-A (BPA) based linear oligomer and 3,3′,3″-triallyl-1,1,1-tris(4-hydroxyphenyl) ethane (triallyl-THPE) through an interfacial polymerization process. Triallyl-THPE consisted of reactive tri-phenoxy and tri-allyl functional groups. The effects of the branching concentration and grafting chain length were examined. The branched grafted silicone polycarbonates (BrSi-PC) and their active precursors (Br-Allyl-PC) showed different thermal properties compared to bisphenol-A polycarbonate (BPA-PC) or linear polycarbonate. BrSi-PC also exhibited superior flow properties, better thermal stability, lower wettability and a different surface morphology compared to those of their precursors, BPA-PC, and branched polycarbonate.