Synthesis, characterization, thermal, and flame retardant properties of phosphate-based epoxy resins

A new phosphorus-containing oxirane bis-glycidyl phenylphosphate (BGPP), and a diamine, bis(4-aminophenyl)phenylphosphate (BAPP), were synthesized. Both of these two phosphorus-containing compounds lead to phosphate-containing epoxy resin via curing reaction. The kinetics of the curing reaction of BGPP with various curing agents, including BAPP, were studied. The introduction of electron-withdrawing group into the compounds increases the BGPP and decreases the BAPP reactivity in the curing reaction. The thermal and the weight loss behavior of the cured epoxy resins were studied by TGA. High char yields (32-52%) as well as high limiting oxygen index (LOI) values (34-49) of these phosphorylated resins were found, confirming the usefulness of these phosphorus-containing epoxy resins as flame retardants. (C) 1997 John Wiley & Sons, Inc.