摘要
为提高聚脲弹性体(PUA)的阻燃性能,采用次磷酸铝(AHP)制备阻燃PUA,并通过热重分析、极限氧指数、垂直燃烧测试、锥形量热测试、扫描电镜、热重-红外联用测试、拉伸、撕裂等一系列测试对阻燃聚脲热性能、阻燃性能、力学性能及阻燃机理进行了系统研究.结果表明,AHP对PUA具有较高的阻燃效率,在20％添加量下,PUA在垂直燃烧测试中表现出离火自熄性,熔滴现象消失,通过UL-94 V-0等级.同时,其热释放速率峰值、总热释放、总烟释放等火安全行为参数大幅下降.残炭微观形貌及气相热解产物分析表明,阻燃PUA燃烧后表面形成了更为致密紧凑的炭层,有效抑制了热解PUA基材中烃类、CO2、CO等物质的生成.力学性能测试结果表明,AHP的加入造成的PUA拉伸强度、断裂伸长率、撕裂强度的损失在可接受范围以内,阻燃PUA在168 h热氧老化处理后仍具有较高的力学性能.
Abstract
In order to improve the flame retardancy of polyurea elastomer(PUA),aluminum hypophosphate(AHP)was used to prepare flame retardant PUA.The thermal performance,flame retardancy,mechanical properties,and flame retardancy mecha-nism of flame retardant polyurea were systematically studied through a series of tests such as thermogravimetric analysis,ulti-mate oxygen index,vertical combustion,cone calorimetry,scan-ning electron microscopy,thermogravimetric infrared spectros-copy,stretching,and tearing.The results indicate that AHP has a high flame retardant efficiency on PUA.At a 20％addition,PUA exhibits self extinguishing properties in vertical combustion tests,and the droplet phenomenon disappears,passing the UL-94 V-0 rating.At the same time,the peak heat release rate,total heat release,total smoke release and other fire safety behavior pa-rameters have significantly decreased.The microstructure and gas phase pyrolysis product analysis of residual carbon indicate that a denser and compact carbon layer is formed on the surface of flame-retardant PUA after combustion,effectively suppressing the generation of hydrocarbons,CO2,CO and other substances in the pyrolysis PUA substrate.The mechanical performance test re-sults show that the addition of AHP has an acceptable loss in ten-sile strength,elongation at break,and tear strength of PUA.Flame retardant PUA still shows high mechanical properties after 168 hours of thermal oxygen aging treatment.
基金项目
国家重点研发计划项目(2021YFB3700202)
维普
万方数据