次磷酸铈对聚丙烯的协同阻燃及耐热氧老化研究OA

This work investigates the synergistic effect of cerium hypophosphite(CeHP)on improving flame retardancy and thermo-oxidative aging resistance of polypropylene(PP).An intumescent flame retardant(IFR)system composed of ammonium polyphosphate and triazine charring-foaming agent at a mass ratio of 4∶1 was constructed as the base formu-lation.When loaded with 22 wt%IFR alone,the resulting PP/IFR composites passed the UL 94 V-0 rating in vertical burning tests.Upon introducing CeHP as a synergist,the optimal performance was achieved at an IFR-to-CeHP mass ra-tio of 93∶7.At a total flame retardant loading of 20 wt%,the PP/IFR/CeHP composites satisfied the UL 94 V-0 rating with a limiting oxygen index of 33.5%.Cone calorimetry tests revealed that,compared to PP/IFR with the same addi-tive loading,the total heat release and total smoke release of PP/IFR/CeHP decreased by 23.7%and 24.8%,respec-tively.This indicates that CeHP promotes char layer formation and significantly reduces heat and smoke release,thereby greatly enhancing the fire safety of PP.Furthermore,after accelerated thermo-oxidative aging at 120℃for 144 h,the mechanical properties of PP/IFR composites deteriorated markedly.In contrast,the PP/IFR/CeHP composites main-tained excellent mechanical retention,demonstrating that CeHP is effective in improving the long-term thermal stability and aging resistance of the composites.