SYNTHESIS, CHARACTERIZATION, THERMAL AND FLAME-RETARDANT PROPERTIES OF NOVEL ARYL PHOSPHINATE DIGLYCIDYL ETHER CURED WITH ANHYDRIDE

A novel aryl phosphinate diglycidyl ether, 10-(2',5'-diglycidyl ether 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DHQEP), was synthe sized. The structure of the diglycidyl ether was characterized by elem ental analysis, mass, FTIR,H-1,C-13, P-31 NMR spectroscopies and X-ray single crystal analysis. In addition, compositions of the diglycidyl ether with three curing agents, e.g. phthalic anhydride (PA), hexahydr ophthalic anhydride (HHPA), and aryl phosphinate anhydride (DMSA), wer e used for making a comparison of its heat and flame retardancy with t hat of DER331 and DEN438. The resulting aryl phosphinate epoxy-resin c omposites demonstrated a higher limiting oxygen index (LOI) value as w ell as a higher char yield, confirming the effectiveness of aryl phosp hinate epoxide as a flame retardant for epoxy resins.