一种磷–氮系阻燃剂的制备及其性能

Preparation and Properties of A Phosphorus-Nitrogen Flame Retardant

采用一步法制备一种P-N系阻燃剂焦磷酸哌嗪(PPAP)。以H3PO4和无水哌嗪为原材料,H3PO4在高温条件下发生脱水反应,生成焦磷酸,与无水哌嗪反应制备焦磷酸哌嗪,制备一种P-N系PPAP,合成工艺简单方便。利用傅立叶变换红外光谱表征合成产物结构。经证明,合成产物是焦磷酸哌嗪。通过热重分析研究PPAP的热稳定性能和成炭性能。结果表明,PPAP的初始分解温度为291.52℃,质量保持率为15.4%。将所制备的PPAP应用在玻纤(GF)增强PP中,PP/GF复合材料的垂直燃烧达到V-0级,极限氧指数增加到28.45%,阻燃性能得到明显提高。力学性能结果表明,掺杂PPAP的PP/GF复合材料的拉伸强度、简支梁缺口冲击强度和弯曲强度较纯PP/GF复合材料下降,弯曲弹性模量和断裂伸长率有所增加。

Halogen free nitrogen-phosphorous flame retardants piperazine pyrophosphate(PPAP)were prepared by one-step method.H3PO4 and anhydrous piperazine were used as raw materials,H3PO4 dehydration reaction under high temperature conditions,pyrophosphoric acid was formed,and piperazine pyrophosphate was prepared by reacting pyrophosphoric acid with anhydrous piperazine to prepare a P-N-based PPAP.The synthesis process is simple and convenient.The structure of the synthesized product was characterized by Fourier transform infrared spectroscopy(FTIR),and it was confirmed that the synthesized product was piperazine pyrophosphate.The thermal stability and char forming properties of PPAP were studied by thermogravimetric analysis.The results show that the initial decomposition temperature of PPAP is 291.52℃and the quatility retention is 15.4%.The prepared PPAP is applied to glass fiber reinforced PP.The vertical burning of PP/GF compoiste UL 94 reaches V-0 level,the LOI increases to 28.45%,and the flame retardant performance is significantly improved.The mechanical properties show that the tensile strength,notched impact and flexural strength of PP/GF dope with PPAP are lower than those of pure PP/GF,and the flexural modulus and elongation at break are increased.