Preparation and properties of wear-resistant and flame-retardant polyphenylsulfoneurea/monomer casting nylon copolymers

A poly(phenylsulfone)-urea (PPSUU) macro-activator is synthesized by in situ anionic polymerization of 4,4′-diaminodiphenylsulfone and hexamethylene diisocyanate. The PPSUU segment is embedded into the nylon molecular chain through copolymerization to improve the wear resistance and flame retardancy of monomer cast nylon 6 (MC PA6) materials. The mechanical properties, thermal stability, friction and wear properties and combustion heat release rate of copolymers with different macro-activator contents are tested. Results indicate that a small amount of PPSUU can improve the wear resistance and impact properties of nylon materials. The wear loss of MC nylon is 54.8% less than pure MC nylon from 1.049 × 10 −8 to 0.474 × 10 −8 g/Nm with 6 wt% PPSUU. Moreover, better flame retardancy is verified. The peak of HRR reduced 36.8% from 654 to 413 kw/m 2 with 4 wt% PPSUU, accompanied by advanced ignition time and flame extinction time, thus reducing the risk of fire.