Synthesis and Physical Properties of Tetramethylcyclobutanediol Polycarbonates

摘要

Polycarbonates from l,l,3,3-tetramelhylcyclobutane-2,4-diol (TMCBD) have been prepared via transesterification reactions with diphenyl carbonate, and evaluated as UV-transparent, weatherable polymers. Melting and glass transition behavior was found to be related to trans content in the polymer. In melt transesterifications, the trans content decreased with long reaction time, due to a ring-opening decomposition reaction. However, high trans content could be maintained by preparing oligomers in the melt, followed by solid state polymerization to high molecular weight.