兼具阻燃和导热性能的环氧树脂复合材料：石墨烯纳米片杂化三聚氰胺磷酸盐的作用

研发制备低成本、少缺陷及高效率的石墨烯纳米片杂化阻燃剂对实现复合材料多功能性具有重要意义。以三聚氰胺为助剥离剂将微粉石墨(GRA)经机械球磨后与磷酸液相反应得到一种阻燃导热的石墨烯纳米片杂化三聚氰胺磷酸盐(GMP)，在表征GMP形貌、结构、组成和热稳定性的基础上，研究了添加GMP环氧树脂(EP)复合材料的阻燃、热分解和导热性能。GMP的热失重分析结果表明：与三聚氰胺磷酸盐(MP)相比，初始分解温度提升了29.3℃，与环氧树脂的热分解温度更匹配，有助于提高阻燃效率。氧指数仪、锥形量热仪和导热性能研究表明，GMP添加30wt%时，EP复合材料的极限氧指数达到了30.4%,UL 94垂直燃烧达到V-0级，峰值热释放速率(PHRR)和峰值烟释放速率(PSPR)分别下降69%和74.0%；导热系数提升至2.10 W·m^-1·K^-1,相对于EP提升了708%。这是由于GMP中石墨烯纳米片(GNPs)与MP的相互作用促进了EP形成了致密的膨胀炭层，有效提高了EP复合材料的阻燃性；随着GMP添加量的增加，GNPs和石墨微片传热通道的形成改善了EP复合材料的导...

Epoxy resin composites with flame retardancy and thermal conductivity: Effect of graphene nanoplatelets hybridized with melamine phosphate

The development and preparation of low-cost, defect less and high-efficiency graphene nanoplatelets hybrid flame retardant is of great significance to achieve the multifunctionality of composites. A graphene nanoplatelets hybrid melamine phosphate flame retardant (GMP) with flame retardant and thermal conductivity was prepared by the reaction of powder graphite (GRA) with phosphoric acid liquid phase after mechanical ball milling with melamine as a stripping agent. The morphology, structure, composition and thermal stability of GMP were characterized. The flame retardant, thermal decomposition and thermal conductivity of GMP epoxy resin (EP) composites were studied. Thermogravimetric analysis show that the initial decomposition temperature of GMP increases 29.3℃ from melamine phosphate (MP), which matches more with EP, contributing to the improvement of flame retardant efficiency of this EP composites. The results show that when the addition of GMP reaches 30wt%, EP composites achieve the limit oxygen index of 30.4%, the vertical combustion of UL 94 reached V-0 level, the peak heat release rate (PHRR) decreases by, and the peak smoke release rate (PSPR) decreased by 69% and 74.0% respectively. The thermal conductivity increases to 2.10 W·m?1·K?1, which is increased by 708% compared with EP. This is because the interaction between graphene nanoplatelets (GNPs) and MP in GMP promote the formation of dense expanded carbon layer on EP, which effectively improves the flame retardancy of EP composites. With the increase of GMP content, the thermal conductivity of EP composite is improved by the formation of GNPs and graphite heat transfer channel. The research provides an idea for the design and preparation of graphene nanoplatelets hybrid flame retardants with both flame retardancy and thermal conductivity to solve the fire hazard caused by thermal deposition of EP composites.