Synthesis, thermal stability, and flame retardancy of PA66, treated with dichlorophenylphsophine derivatives

Synthesis, thermal stability, and flame retardancy of PA66, treated with derivatives of dichlorophenylphosphine, are reported. With an aim to improve the thermal stability and flame retardancy of PA66, along with improving its consistency, several new derivatives of dichlorophenylphosphine, namely bis-(4-carboxyanilino) phenyl phosphamide (BNPO), N-benzoic acid-(ethyl-N-benzoic acid formamide) phosphamide (NENP), poly-N-aniline-phenyl phosphamide (DPPD), and bis-N-benzoguanamine-phenyl phosphamide (MCPO), were synthesized, which resulted in end amino or carboxyl. FTIR, 1H NMR, MS, and elemental analysis confirmed the chemical structures of the synthesized flame retardants. Interestingly, thermal stabilities and flame retardancies of PA66 improved, however, the intrinsic viscosities ([η]) and viscosity average molecular weights (Mη) decreased with grafting of the flame retardants. Moreover, the consistency was overcome conformingly using SEM without interfacial effect.