无卤磷腈阻燃剂的合成及在PVC中的应用

Synthesis of Flame Retardant Trimer O,O-2-Hydroxypropyl Phosphazene and Application in PVC

以六氯环三磷腈和丙三醇为原料,一步反应合成了一种新型无卤磷氮协同阻燃剂——三聚O,O-2-羟基丙撑磷腈,合成工艺简单方便。通过傅里叶变换红外光谱、核磁共振氢谱等表征产物的结构,证明合成产物为目标产物。考察了溶剂、反应温度及反应时间对产率的影响,确定最佳工艺条件,即氮气保护下,以二氧六环为溶剂,N,N-二甲基苯胺为缚酸剂,六氯环三磷腈与丙三醇物质的量比为1∶3,于100℃反应15 h。合成三聚O,O-2-羟基丙撑磷腈的产率为95.8%,分解温度为(280±5)℃,耐高温性能优异。将其用于聚氯乙烯阻燃,当添加量为4.88%时,极限氧指数即达28%,具有良好的阻燃效果,残炭扫描电子显微镜表征分析结果表明,残炭结构能进一步起到阻燃作用。

A new type of halogen-free phosphorus-nitrogen synergistic flame retardant was synthesized in one step,namely trimer O,O-2-hydroxypropyl phosphazene,using hexachlorocyclotriphosphazene and glycerol as raw materials,and the synthesis process was simple and convenient.The chemical structure of the product was characterized by FTIR and 1H-NMR,and it was confirmed that the synthesized product was trimer O,O-2-hydroxypropyl phosphazene.The influence of solvent,reaction temperature and time on the yield were also investigated.The optimum conditions were as follows,under the protection of nitrogen,n(hexachlorocyclotriphosphazene)∶n(glycerol)=1∶3,dissolving in dioxane,N,N-dimethylaniline being used as acid binding agent and keeping reaction at 100℃for 15 h.The yield of the product was 95.8%.The decomposition temperature was(280±5)℃,which meant it had excellent high temperature resistance.The limiting oxygen index reached 28%,when its addition amount was 4.88%in PVC flame retardant,which had a good flame retardant effect.The SEM characterization analysis results of residual carbon showed that the residual carbon structure could further play a flame retardant effect.