摘要
采用聚碳硅烷(PCS)改性氢氧化镁(MH)作为无卤阻燃剂(PCS/MH),通过熔融共混法制备了无卤阻燃聚丙烯复合材料(PPMC),采用红外光谱(FTIR)分析了PCS/MH的结构;采用氧指数(LOI)研究了复合材料的阻燃性能,并采用锥形量热仪(CONE)研究了复合材料的燃烧行为;采用热重分析(TGA)研究复合材料的热降解行为,采用扫描电子显微镜(SEM)研究了残炭的微观结构。研究结果显示,在阻燃剂添加质量为60%时,PPMC的氧指数可达到29.7%,与MH阻燃聚丙烯复合材料(PPM)相比,提高了11.2%,具有显著的协同阻燃效果。PPMC的热释放峰值(pHRR)与PPM相比增加了53.7%,为256.7 kW/m^2,但到达pHRR所用时间延长了145s,同时在燃烧初期阶段热释放量和质量损失受到显著抑制,表明其炭层具有良好的热稳定性和阻隔作用。TG和SEM的结果进一步揭示了PPMC阻燃性能的改善关键在于炭层表面形成致密的保护层。
The halogen-free flame retardant was prepared by surface modification of magnesium hydroxide(MH)with polycarbosilane(PCS).The halogen-free flame retardant polypropylene composites(PPMC)were prepared by melt blending of PP and PCS/MH.Fourier transform infrared spectroscopy(FT-IR)was used to analyze the structure of PCS/MH.The flame retardant properties and combustion behaviors of the composites were evaluated by limiting oxygen index(LOI)and CONE calorimeter,respectively.The thermal degradation process of the composites was characterized by thermogravimetric analysis(TGA)and the microstructure of the residual char was characterized by scanning electron microscopy(SEM).The results revealed the synergistic effect between MH and PCS in flame retardant PP composites.The LOI of PPMC with 60%MH/PCS was 29.7%,which was 11.2%higher than that of MH/PP composites(PPM)at the same flame retardant loading.The results from CONE revealed that the heat release and mass loss were inhibited apparently during the initial stage of combustion.The char with good thermal stability and barrier effect prolonged the time to peak heat release rate of PPMC,which was 145 s longer than that of PPM.The improved flame retardant properties of PPMC were attributed to a cohesive protective layer on the surface of the residue,based on the microstructure of the residue and thermal stability of PPMC by SEM and TGA.
作者
张立飞
王春锋
韩志东
ZHANG Lifei;WANG Chunfeng;HAN Zhidong(School of Materials Science and Engineering, Harbin University of Scienceand Technology, Harbin 150080, China)
出处
《功能材料》
EI
CAS
CSCD
北大核心
2020年第7期7069-7073,7082,共6页
Journal of Functional Materials
基金
国家自然科学基金资助项目(50802022)
黑龙江省自然基金资助项目(E2018040)。
关键词
聚丙烯
氢氧化镁
聚碳硅烷
阻燃性能
polypropylene
magnesium hydroxide
polycarbosilane
flame retardant properties
