CHEMICAL MODIFICATION OF BISPHENOL A POLYCARBONATE BY REACTIVE BLENDING WITH CYCLIC ALIPHATIC CARBONATES

摘要

On the light of the increasing importance of the melt polymerization process for the synthesis of Bisphenol A polycarbonate (PC), because does not require the use of phosgene, we carried out a wide study regarding the insertion of aliphatic moieties into PC backbone by exchange reaction in the melt. By this way we have obtained new polymeric materials with modified thermal and Theological properties. The insertion of aliphatic groups into PC polymer chain is industrially used to control glass transition temperature (T_g). The decreased T_g leads to lower melt viscosity and thus better processability of the melt material. AH of the methods industrially available up to now are related to interfacial polymerization of PC. The process to insert aliphatic groups into PC backbone, described in this communication, is based on the reactive blending of cyclic aliphatic carbonates, such as ethylene carbonate (ETC), propylene carbonate (PRC) or neopentylene carbonate (NPC) with PC.