MECHANICAL-PROPERTIES OF EPOXY-RESINS CURED WITH P3N3(NH2)2(OC6H4CL)4

l,l-Diamino-3,3,5,5-tetra(p-chlorophenoxy)cyclotriphosphazene (ACPP) was used as a curing agent for epoxy resins. The mechanical properties of the cured epoxy resins were examined by torsion pendulum analysis and compared with those of the epoxy resins cured with l,l-diamino-3,3,5,5-tetraphenoxycyclotriphosphazene (PC 10). ACPP was prepared from hexachlorocyclotriphosphazene by the method of Kajiwara et al. The yield of ACPP was higher than that of PC 10, and ACPP could precure the epoxy resins in a shorter time. The epoxy resin cured with PC 10 exhibited higher modulus of rigidity at around room temperature than that cured with m-phenylenediamine. Although the modulus of rigidity of the epoxy resin cured with PC 10 decreased remarkably with increasing temperature, the epoxy resin cured with ACPP kept the high modulus up to about 150°C. The epoxy resin cured with ACPP also showed superior resistance to alkaline immersion, while that cured with PC 10 degraded. It is concluded that ACPP is an effective curing agent for epoxy resins to enhance the modulus of rigidity below 150°C and resistance to alkali. © 1990, The Society of Polymer Science, Japan. All rights reserved.