磷氮阻燃剂PDAB-DOPO的制备及阻燃环氧树脂复合材料性能研究

Preparation of phosphorus-nitrogen PDAB-DOPO and its flame retardant epoxy resin

以对苯二胺、9,10-2H-9-氧杂-10-磷杂菲-10-氧化物(DOPO)、四氯化碳为原料制备磷氮阻燃剂6,6′-(1,4-亚苯基双(氮烷二基)双(6H-二苯并[c,e][1,2]氧杂磷苯-6-氧化物)(PDAB-DOPO)。利用傅里叶变换红外光谱仪、核磁共振氢谱仪对PDAB-DOPO结构进行了表征并将其用于阻燃环氧树脂;通过热失重分析对PDAB-DOPO及环氧树脂复合材料的热性能进行了表征,通过极限氧指数(LOI)和UL94测试对环氧树脂复合材料阻燃性能进行了表征,通过扫描电子显微镜对环氧树脂复合材料残炭形貌进行了分析。结果表明:当体系中磷质量分数为1.65%时,800℃时环氧树脂复合材料残炭量提高到18.9%,环氧树脂复合材料体系的LOI为27.3%,通过UL 94V-0级测试。扫描电子显微镜分析表明,PDAB-DOPO的加入使得环氧树脂体系残炭表面形貌发生明显变化,PDAB-DOPO对环氧树脂具有良好的阻燃效果。

The phosphorus-nitrogen flame retardant 6,6′-(p-phenylenediamine-1,4-diyl)bis(6 H-dibenzo[c,e][1,2]oxophosphate-6-oxide)(PDAB-DOPO) was synthesized using p-phenylenediamine,9,10-2 H-9-oxa-10-phospaphenanthrene-10-oxide(DOPO)and carbon tetrachloride as raw materials.The structure was characterized using FT-IR and 1 H-NMR,and the flame retard epoxy resin(EP)was prepared using PDAB-DOPO as flame retardant.The thermal properties of PDAB-DOPO and cured products were investigated by TGA,flame retardant properties was characterized by limit oxygen index(LOI)and vertical burning test(UL 94),and the residual carbon morphology was investigated by SEM.TGA results indicated that when the phosphorus content reached 1.65% in the EP system,the carbon residue rate can reached 18.9% at 800℃.LOI reached 27.3%,UL 94 passed V-0 level.And SEM results revealed that the addition of PDAB-DOPO can obviously improve the carbon residue morphology after combustion,and PDAB-DOPO can enhance the flame retardant properties of epoxy resin.