Synthesis of ultra high-molecular-weight polycarbonate

Solid-state thermal polymerization of isolated Bisphenol A type macrocyclic oligocarbonates was carried out. The ring-opening polymerization progresse d without any catalyst. Dimer (c-2mer) could be completely converted to the corresponding aromatic polycarbonate by heating at 300 degreesC for 10 min . In case of trimer (c-3mer), a small part of c-3mer remained unpolymerized even after heating for 30 min at 300 degreesC and complete conversion of t etramer (c-4mer) could not be achieved even in 120 min. Although the c-4mer exhibited much lower reactivity than c-2mer and c-3mer, ifs conversion was drastically improved by the addition of the c-2mer. The lower reactivity o f the larger oligomer may be due to slower initiation of the larger ring. T he ultra high-molecular-weight polymers (M-w > 1,000,000) were soluble in c hloroform. Copyright (C) 2000 John Wiley & Sons, Ltd.