含磷聚硅氮烷聚合物的制备及热稳定性能与阻燃应用

Preparation,Thermal Stability and Flame Retardant Application of Phosphorous-Containing Polysilazane

通过含乙烯基聚硅氮烷(PVSZ)和9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO)的加成反应,合成一种新型含磷聚硅氮烷聚合物PPVSZ。采用红外光谱、核磁共振氢谱对其结构进行了表征,利用差示扫描量热分析和热重分析研究了PPVSZ固化行为和热稳定性能,通过扫描电镜对PPVSZ固化物的微观结构进行了研究,利用垂直燃烧和极限氧指数探究其对环氧树脂的阻燃应用。结果表明,PPVSZ能在一定的温度下发生交联反应,固化物能够形成完整致密的结构,具有良好的热稳定性能,在N2和空气氛围下质量损失5%时的温度均高于400℃,800℃的质量保留率都大于75%。此外,在环氧树脂中添加量为2.5%时,极限氧指数达到30%,垂直燃烧通过了UL-94的V-0等级。

A novel phosphorus-containing polysilazane was synthesized through the reaction between polysilazane(PVSZ)and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide(DOPO).The structure of PPVSZ was characterized by FT-IR and^1H-NMR.The curing behavior and thermal stability of PPVSZ were studied by DSC and TGA,respectively.The microstructure of cured PPVSZ was studied by SEM.After that,the vertical combustion and limiting oxygen index were used to explore its flame resistance application in epoxy resin.The results show that the crosslinking reaction of PPVSZ can occur at a certain temperature.The cured PPVSZ forms a complete and dense structure and has excellent thermal stability.The 5%mass loss temperatures under nitrogen and air is up to 400℃,and the residue at 800℃is higher than 75%.In addition,the epoxy resin with as low as 2.5%PPVSZ could achieve V-0 rating in the UL-94 test and the limited oxygen index is 30%.