KH550改性PEPA对PP/IFR体系阻燃、耐水和力学性能的影响

Improving the Flame Retardancy,Water Resistance and Mechanical Properties of PP/IFR Composites by Introducing KH550 Modified PEPA

利用硅烷偶联剂KH550对季戊四醇磷酸酯(PEPA)进行表面改性,得到Si-PEPA,将其与三聚氰胺聚磷酸盐(MPP)复配成膨胀型阻燃剂(IFR)对聚丙烯(PP)进行阻燃改性。研究了KH550改性PEPA对PP/IFR体系阻燃、耐水和力学性能的影响。利用极限氧指数(LOI)仪、垂直燃烧(UL94)仪、锥形量热(CONE)仪对阻燃PP的燃烧性能进行测试,结果表明,当IFR的添加量为20%时,PP/MPP/Si-PEPA体系可以达到UL94 V-0级,氧指数达到32.5%,最大热释放速率(PHRR)和总热释放量(THR)都较PP/MPP/PEPA体系有明显降低。热重分析(TGA)显示,经KH550处理后,PP/IFR材料的热稳定性显著提高。经70℃热水浸泡72 h后,PP/MPP/Si-PEPA材料仍然可以通过UL94 V-1级。同时,KH550对PEPA的表面处理也提高了PP/IFR材料的力学强度。

The surface of pentaerythritol octahydrogen tetraphosphate （PEPA） was modified by silane coupling agent KH550 to produce Si-PEPA which was then introduced into polypropylene （PP） together with melamine polyphosphate （MPP） to prepare intumescent flame retardant PP composites. The effects of KH550 modified PEPA on the fire performance, water resistance and mechanical properties of PP/IFR composites were studied. The results from flammability characterization by limiting oxygen index （LOI）, UL- 94 measurement and cone calorimeter （CONE） test demonstrate that the PP/MPP/Si-PEPA composites could reach UL94 V-0 flammability rating based on the 20% loading of IFR, the LOI value is improved to 32.5% , the peak heat release rate （PHRR） and total heat release （THR） are significantly decreased compared with PP/MPP/PEPA composites. The TGA analysis indicates that the thermal stability of PP/IFR composites is improved significantly after the modification by KH550. The PP/MPP/Si-PEPA composites could pass the UL94 V-1 flammability rating after soaking in hot water at 70 ℃ for 72 h, while the PP/MPP/PEPA composites failed. The tensile strength of PP/IFR is also improved after the modification by KH550.