Polyurea elastomer with aluminum hypophosphite:flame retardancy and aging resistance
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.
万方数据
维普
