Polycarbonate was blended with zinc, zinc borate (2ZnO·3B 2 O 3 ·3.5H 2 O) and zinc oxide. Blends made of zinc/polycarbonate and especially zinc borate/polycarbonate show major improvement in oxygen index values. Ohio State University (OSU) heat release studies show reduction in heat release only for zinc borate/polycarbonate blends compared to virgin polycarbonate. No improvement in smoke suppression was observed from NBS Smoke Chamber studies for these blends. From DSC studies there was a low ering of Tg's. Thermogravimetric analyses show the blends have lower tempera ture stability in nitrogen (50% weight loss) compared to a control.