硅烷改性ADP对PP力学性能与阻燃性能的影响

Effect of Silane Modified ADP on Mechanical Properties and Flame Retardancy of PP

为适应电缆、电子电器等领域对材料防火安全方面的要求,对阻燃聚丙烯复合材料的研究得到广泛关注。针对二乙基次膦酸铝(ADP)对聚丙烯(PP)阻燃效果的问题,使用干法改性的方法,以硅烷偶联剂A-151、KH-550、KH-560对ADP进行表面改性,探究其对PP的力学性能与阻燃性能的影响。结果表明:使用携带乙烯基官能团的A-151改性可以提高ADP与PP的相容性,提高复合材料的力学性能与阻燃性能,PP/20ADP的极限氧指数(LOI)仅为20.0%,PP/20VADP达到27.3%,提升36.5%。在阻燃剂添加质量分数为20%时,3种改性ADP中,使用KH-560改性ADP的复合材料的热释放速率峰值(pHRR)和总热释放量(THR)最低,相比,PP/20ADP,pHRR提高2.2%,但THR降低10.5%,这是因为KH-560携带的环氧基官能团能与ADP起到协同阻燃作用,从而提高阻燃性。文章以高硅烷添加量揭示了硅烷改性ADP对PP的阻燃机理。

In order to meet the fire safety requirements of materials in the fields of cables,electronic appliances,etc.,the research of flame retardant polypropylene composites has been widely concerned.Aiming at the flame retardant effect of aluminum diethylphosphinate(ADP)on polypropylene(PP),the article used a dry modification method to modify the surface of ADP with silane coupling agents A-151,KH-550,and KH-560,explores their influence on the mechanical and flame retardancy of PP.The results show that under the same amount of addition,the modification of A-151 with vinyl functional group can improve the compatibility of ADP and PP,and improve the mechanical properties and flame retardancy of the composites,the limited oxygen index(LOI)of PP/20ADP is only 20.0%,and that of PP/20VADP is 27.3%,with an increase of 36.5%.Among the three modified ADPs,the composite with KH-560 modified ADP has the lowest peak heat release rate(pHRR)and total heat release(THR)when the adding mass fraction of flame retardant is 20%,compared with PP/20ADP,the pHRR is increased by 2.2%,but the THR is decreased by 10.5%.The reason is that the epoxide functional group carried by KH-560 can play a synergistic flame retardancy with ADP,thus improving the flame retardancy.In this paper,the flame retardancy mechanism of silane-modified ADP on PP is revealed with high silane addition amount.