DOPO-PHBA反应型阻燃剂的合成及其与TGIC复配体系对环氧树脂性能的影响

以9，10-二氢-9-氧杂-10-磷杂菲-10-氧化物（DOPO）和对羟基苯甲醛（PHBA）为主要原料，合成了一种新型的反应型阻燃剂DOPO-PHBA，利用FTIR和核磁共振谱（¹H-NMR、³¹P-NMR）对其分子结构和组成进行了分析表征。将DOPO-PHBA与异氰尿酸三缩水甘油酯（TGIC）复配用于制备DOPO-PHBA-TGIC/环氧树脂（EP）复合材料，通过极限氧指数（LOI）、动态热机械测试（DMA）和TGA分别对DOPO-PHBA-TGIC/EP复合材料的阻燃性能和热性能进行了研究。结果表明：成功制备了DOPO-PHBA，且DOPO-PHBA-TGIC复配型阻燃剂能显著改善EP的阻燃性能，当体系磷元素的质量分数为0.6wt%时，氧指数（LOI）由24%提高至32.5%；此外不同磷含量的DOPO-PHBA-TGIC/EP复合材料的玻璃化转变温度（T_g）均保持在200℃以上并且在800℃时的残炭量不断提高，其初始分解温度和最大热失重速率均有所下降；燃烧后残炭的红外分析表明，该体系满足凝聚相阻燃机制，且DOPO-PHBA-TGIC的加入不会削弱EP的力学性能。

Synthesis of DOPO-PHBA reactive flame retardant and its effect on properties of epoxy resin with TGIC

A novel reactive flame retardant (DOPO-PHBA) was synthesized by the reaction between 9,10-dihydro-9-oxa-10-phosphine-10-oxide (DOPO) and p-hydroxybenzaldehyde (PHBA).Its structure and composition were characterized by FTIR and nuclear magnetic resonance spectroscopy ¹H-NMR and ³¹P-NMR. DOPO-PHBA was compounded with triglycidyl isocyanurate (TGIC) to prepare DOPO-PHBA-TGIC/epoxy resin(EP) composites. The flame retardancy and thermal properties of DOPO-PHBA-TGIC/EP composites were respectively investigated by limiting oxygen index (LOI), dynamic mechanical analysis (DMA) and thermogravimetric analysis. Results indicate that DOPO-PHBA is successfully synthesized. The addition of DOPO-PHBA-TGIC can significantly enhance the flame retardancy of EP resin, while the mass fraction of phosphorus is 0.6wt%, LOI value increases from 24% to 32.5%. Additionally, the glass transition temperature (T_g) of DOPO-PHBA-TGIC/EP composites with different phosphorus mass fractions are maintained at 200℃ or higher, and the residues at 800℃ under nitrogen atmosphere are increased. But the initial degradation temperatures and maximum decomposition rates of DOPO-PHBA-TGIC/EP composites are decreased. FTIR analysis of char residues reveal that this flame retardant system satisfies condensed phase flame retardant mechanism, and the incorporation of DOPO-PHBA-TGIC does not impair the physical property of EP resin.