改性鸡蛋壳协效膨胀型阻燃剂对热塑性聚氨酯弹性体阻燃抑烟性能的影响

Effect of modified chicken eggshell and intumescent flame retardant on flame retardancy and smoke suppression of thermoplastic polyurethane elastomer

为了提高热塑性聚氨酯弹性体(TPU)的阻燃抑烟性能,以废弃鸡蛋壳(CES)为原料,采用沸石咪唑酯骨架材料-8(ZIF-8)对其改性,合成了ZIF-8-CES杂化物。与纯TPU相比,当TPU中添加20wt%膨胀型阻燃剂(IFR)和5wt%ZIF-8-CES时,TPU复合材料的热释放速率峰值(pHRR)和烟释放速率峰值(pSPR)分别降低到242 kW·m^(−2)和0.151 m^(2)·s^(−1),极限氧指数(LOI)值到达31.5%,垂直燃烧(UL-94)达到了V-0级,ZIF-8-CES与IFR在TPU中具有较好的协效阻燃效果。这主要是由于ZIF-8-CES与IFR在高温下生成氧化锌、磷酸钙和亚磷酸钙,起到催化成炭和增强炭层的作用,从而提高了TPU复合材料的阻燃、抑烟性能。

In order to improve the flame retardant and smoke suppression properties of thermoplastic polyurethane elastomer(TPU),ZIF-8-CES hybrid was synthesized by using waste chicken eggshell(CES)as raw material and modified by zeolitic imidazolate framework-8(ZIF-8).Compared with pure TPU,when 20wt%intumescent flame retardant(IFR)and 5wt%ZIF-8-CES are added to TPU,the peak heat release rate(pHRR)and peak smoke release rate(pSPR)of TPU composites are reduced to 242 kW·m^(−2)and 0.151 m^(2)·s^(−1),respectively.The limiting oxygen index(LOI)value reached 31.5%,and the vertical combustion(UL-94)reached V-0 level.ZIF-8-CES and IFR have good synergistic flame retardant effect in TPU.This is mainly because ZIF-8-CES and IFR generate zinc oxide,calcium phosphate and calcium phosphite at high temperatures,which play a role in catalyzing carbon formation and enhancing the carbon layer,thereby improving the flame retardant and smoke suppression properties of TPU composites.