硅-磷复配阻燃剂对聚碳酸酯/ASA复合材料阻燃性能及动态力学性能的影响

利用熔融共混法制备多聚芳基磷酸（BDPB）-倍半硅氧烷（SPH）-聚碳酸酯（PC）/丙烯腈-苯乙烯-丙烯酸丁酯的三元共聚物（ASA）、BDPB-有机蒙脱土（OMMT）-PC/ASA两种阻燃增强复合材料。通过XRD、TG、极限氧指数（LOI）、SEM、XPS、DMA等对所制备BDPB-SPH-PC/ASA、BDPB-OMMT-PC/ASA两种复合材料的微观结构、燃烧性能及动态力学性能进行表征。结果表明：BDPB-SPH和BDPB-OMMT两种复配阻燃体系对PC/ASA复合材料都具有优异的阻燃协同作用，BDPB-SPH-PC/ASA和BDPB-OMMT-PC/ASA复合材料的燃烧等级（UL-94）都可以达到V-0级别，LOI分别达到30.4%和31.2%，同时残炭量分别增加至12.43%和14.24%。随着复配阻燃剂BDPB-SPH和BDPB-OMMT的加入，增强后的PC/ASA复合材料的残余炭层结构更加致密与紧凑，燃烧过程中阻燃剂BDPB、SPH和OMMT会迁徙到PC/ASA材料的表面，形成更稳定的保护层，从而提高PC/ASA复合材料阻燃性能。DMA结果表明，BDPB-SPH和BDPB-OMMT两种阻燃体系的加入都会降低PC/ASA复合材料的玻璃化转变温度（T_g），且在到达T_g前可明显提高阻燃复合材料的储能模量。

Flame-retardation synergism and dynamic mechanical properties of polycarbonate/ASA composites modified by silicon and organo-phosphate containing flame retardants

Polycarbonate/acrylonitrile styrene acrylate (PC/ASA) composites modified with two kinds of synergistic flame-retardant systems, p-bis-(diphenylphosphoryloxy)-benzol (BDPB)-silsesquioxanes, phenyl, hydroxy-terminated(SPH) and BDPB-organically modified montmorillonite(OMMT), respectively, were prepared by melt compounding. The microstructure、combustion behavior and dynamic mechanical properties were investigated by XRD, TG, limiting oxygen index(LOI), SEM, XPS and DMA test. The results indicate that the BDPB-SPH and BDPB-OMMT flame-retardant systems exhibit a synergistic effect. The BDPB-SPH-PC/ASA and BDPB-OMMT-PC/ASA composites could reach V-0 rating in vertical burning test (UL-94), and the LOI of the composites reach 30.4% and 31.2%, respectively. The residual of BDPB-SPH-PC/ASA and BDPB-OMMT-PC/ASA could increase to 12.43% and 14.24%, respectively. With the loading of BDPB-SPH and BDPB-OMMT flame-retardant systems, the microstructure of residual layer becomes more compact. BDPB, SPH and OMMT tend to accumulate at the surface during combustion, which could promote the formation of stable layer and as a result enhance the flame retardant properties. The glass transition temperature(T_g) of BDPB-SPH-PC/ASA and BDPB-OMMT-PC/ASA composites shift to low temperature, and the storage modulus of the composites are enhanced before T_g.