玻璃纤维增强聚对苯二甲酸乙二醇酯/次磷酸铈复合材料的制备及其阻燃性能研究

首先合成并表征了一种新的阻燃剂-次磷酸铈（CHP）;然后采用熔融共混的方法制备了玻璃纤维（GF）增强聚对苯二甲酸乙二醇酯（PET）/CHP（PET/GF/CHP）复合材料;探讨了CHP对PET/GF复合材料热稳定性和燃烧性能的影响。材料的热稳定性是由热失重分析（TGA）进行表征的,燃烧性能是通过氧指数（LOI）、垂直燃烧（UL-94）以及锥形量热仪进行测试的,炭渣形貌由扫描电子显微镜（SEM）进行表征。结果表明：CHP的引入保持了PET/GF的热稳定性。含有15wt%CHP的PET/GF材料（PET/GF/CHP15）,其LOI为30%,且能达到UL-94V-0级别。此外,与PET/GF相比,PET/GF/CHP15热释放速率峰值和热释放总量分别下降了67%和27%。SEM分析表明CHP的加入使得材料在燃烧后有大量致密的炭渣覆盖在玻璃纤维的表面,这些炭渣不仅降低了玻璃纤维的导热性,而且切断了可燃物质的传送通道,从而提高了材料的阻燃性能。

Preparation and flame retardant properties of glass-fiber reinforced poly(ethylene terephthalate)/cerium hypophosphite composites

A novel flame retardant,cerium hypophosphite(CHP),was synthesized and characterized.The glass-fiber reinforced poly(ethylene terephthalate)/CHP(PET/GF/CHP) composites were then prepared by means of melt blending method.The thermal stability and combustion properties were respectively studied by thermogravimetric analysis(TGA) and limiting oxygen index(LOI),Underwriters Laboratories 94(UL-94),cone calorimeter testing.The char residues after cone calorimeter testing were investigated by scanning electron microscope(SEM).TGA results illustrated that the incorporation of CHP had no influence on the thermal stability of PET/GF composites.For PET/GF containing 15 wt% of CHP(PET/GF/CHP15),it achieved a V-0 classification with a high LOI(30%).Additionally,the peak heat release rate(PHRR) and total heat release rate(THR) were respectively reduced by around 67% and 27% compared to the results obtained from PET/GF.SEM analysis indicated that many compact char residues were covered on the surface of glass fibers in the SEM image of PET/GF/CHP.The char residues can effectively decrease the heat conduction of glass fibers and cut off the mass transfer path resulting in the enhancement of flame retardancy.