聚磷酸铵/环糊精/硅橡胶复合材料的阻燃性能及热降解动力学

Flame Retardant Properties and Thermal Degradation Kinetics of Ammonium Polyphosphate/Cyclodextrin/Silicone Rubber Composites

以107硅橡胶为基础胶,以环糊精(CD)为膨胀型阻燃剂(IFR)的碳源,聚磷酸铵(APP)为IFR的酸源和气源,制备硅橡胶复合材料(SR).研究了APP/CD阻燃体系对硅橡胶阻燃性和热稳定性的影响;并采用Flynn-Wall-Ozawa(FWO)法计算SR的热降解活化能.结果表明,APP与CD的质量比为3∶1,添加量为40份时,SR的极限氧指数为24.0%,SR的垂直燃烧性能达到UL94 V-0级;APP和CD的加入硅橡胶的热稳定性降低;APP的加入SR的活化能降低明显,这是由于APP促进了硅橡胶的热分解;APP和CD的加入SR的活化能也降低,CD的加入促进了APP提前分解和硅橡胶的成炭,从而进一步降低了硅橡胶的活化能.

Silicone rubber composite(SR)was prepared with 107 silicone rubber as the base material,cyclodextrin(CD)as the carbon source of intumescent flame retardant(IFR)and ammonium polyphosphate(APP)as the acid source and gas source of IFR.The influences of APP/CD flame retardant system on the flame retardancy and thermal stability of silicone rubber were studied.Flynn-wall-ozawa(FWO)method was used to calculate the thermal degradation activation energy of SR.The results showed that the mass ratio of APP to CD was 3∶1,and when the addition amount was 40 PHR,the limit oxygen index of SR was 24.0%,and the vertical combustion performance of SR reached UL94 V-0 level.The thermal stability of silicone rubber was reduced with the addition of APP and CD.The activation energy of SR was significantly reduced with the addition of APP,which was due to the fact that APP promoted the thermal decomposition of silicone rubber.The activation energy of SR was also reduced with the addition of APP and CD.The addition of CD promoted the APP to decompose in advance and the carbonization of silicone rubber,which further reduced the activation energy of SR.