磷酸酯阻燃剂HDP的合成工艺及其在ABS中的阻燃作用

采用新工艺路线合成高熔点磷酸酯阻燃剂———对苯二酚双(二苯基磷酸酯)(HDP).首先采用对苯二酚和三氯氧磷合成中间产物,再将中间产物与苯酚反应,经分离纯化得到产品HDP,收率达到90%以上,常温下为白色固体.采用傅里叶红外光谱、氢谱、磷谱和质谱测试确定了其结构.同时,研究了HDP的阻燃性,并与间苯二酚双(二苯基磷酸酯)(RDP)进行了比较,研究发现当HDP和RDP分别与成炭剂酚醛树脂(NP)按20/10比例添加到丙烯腈-丁二烯-苯乙烯(ABS)树脂中,增强了复合材料凝聚相阻燃作用,极限氧指数(LOI)有所提高.通过热重及锥形量热分析两种复合材料以及各种组分的热降解过程,阻燃剂的添加对ABS树脂的热稳定性和残炭量明显提高,而且ABS/HDP/NP复合材料的抑烟性更好;同时采用扫描电镜(SEM)和X射线能量色散谱(EDS),发现ABS/HDP/NP复合材料燃烧后成炭空隙均匀,其残炭中磷分布比ABS/RDP/NP复合材料残炭中的磷分布更加均匀.研究表明,HDP与NP互配添加到ABS中,在凝聚相阻燃作用优于RDP.

SYNTHESIS AND APPLICATION OF PHOSPHORUS FLAME RETARDANT HDP ABS COMPOSITES

A high melting temperature phosphorus flame retardant,hydroquinol bis(diphenyl phosphate)(HDP),was synthesized in a novel process.First,the intermediate product was synthesized from hydroquinone and phosphoryl oxychloride,and then it was reacted with phenol,at last,HDP was isolated and purified.The obtained HDP was a kind of white solid,and the yield exceeded 90%.The structure of HDP was characterized by 1H-NMR,31P-NMR and MS.The flame retardance of HDP was discussed,and compared with resorcinol bis(diphenyl phosphate)(HDP) in acrylonitrile-butadiene-styrene(ABS) composites.When HDP or RDP was added into ABS resin with char former Novolac phenol(NP) in the ratio of HDP(RDP)/NP(20/10),it was very effective in enhancing the LOI value and improving the flame retardation in condensation phase.The thermal degradation properties were was investigated by thermogravimetric analysis(TGA) and cone calorimeter test,and the results showed that the incorporation of HDP or RDP increased its thermal stability and char formation.The smoke suppression of ABS/HDP/NP composites is better than that of ABS/RDP/NP composites.The morphological structures and element distribution of the chars were investigated by scanning electron microscopy(SEM) and energy dispersive spectroscopy(EDS).Compared with ABS/RDP/NP composites,the cavities and holes were more uniform,and the distribution phosphorus was more uniform in the char of ABS/HDP/NP composites.The above analysis showed that,when HDP was added to ABS resin with NP,HDP had better flame retardancy in condensation phase than RDP.