| Abstract: | Aromatic polycarbonates were prepared from several dichloroformates with phosphorus-containing bisphenols, such as bis(p-hydroxyphenyl)methyl phosphine oxide and bis(p-hydroxyphenyl)phenyl phosphine oxide, or with nonphosphorus bisphenols by interfacial, low-temperature solution, and high-temperature solution polycondensation. The interfacial polycondensation gave the best results for polycarbonates, from which colorless, transparent, and fairly though films were cast. In contrast to analogous nonphosphorus polycarbonates, the phosphorus-containing polycarbonates exhibited lower polymer melt temperatures, greater range of solubility, and better self-extinguishing properties, but less stability to alkali and acid. Thermal degradation of the typical phosphorus polycarbonates proceeded in two steps, and the activation energies for the maximum rates of weight loss range from 29 to 45 kcal/mole. |
