新型含硼苯并噁嗪的合成及其与环氧树脂共混热性能

Synthesis of novel boron containing benzoxazine and its thermal properties with epoxy resin blends

以乙醇胺、硼酸为原料合成硼酸乙醇胺酯(BAE),再用所得硼酸乙醇胺酯与多聚甲醛、苯酚反应,合成含硼苯并噁嗪(BAE-BOZ)。将所得BAE-BOZ高温固化,BAE-BOZ和环氧树脂E-51按照不同的质量比进行熔融共混,并经高温固化。采用FT-IR,~1H NMR和^(13)C NMR等分析了BAE-BOZ的化学结构,证明了产物为目标产物;采用DSC对BAE-BOZ的固化特性进行研究;采用TG分析了含硼乙醇胺型苯并噁嗪poly(BAE-BOZ)和BAE-BOZ/E-51共聚物的热稳定性。结果表明:BAE-BOZ在218℃出现了固化峰;BAE-BOZ的硼含量达到8.67%,在N_2条件下,poly(BAE-BOZ)的热分解温度为302℃,在426℃时热分解速率最快,800℃的残炭率为58.08%,与未经硼改性的乙醇胺型苯并噁嗪(E-BOZ)相比,热分解温度提高40℃,残炭率提高了16.28%;BAE-BOZ/E-51共聚物的热分解温度达到343℃,热性能得到进一步提高。

The boric acid ethanolamine ester （BAE） was synthesized using boric acid and ethanolamine. The synthesis of benzoxazine contained boron （BAE-BOZ） was synthesized by using BAE, phenol and paraformaldehyde The BAE-BOZ are mixed with epoxy resin in different proportions, and then cured by high temperature. Using FT-IR, 1H NMR and 13C NMR analysis of the chemical structure of BAE-BOZ, proved that the target product has been synthesized. Curing properties on BAE-BOZ was studied with DSC, the thermal stability of poly（BAE-BOZ） cured BAE-BOZ/E-51 were studied by using TG analysis. The results showed that the curing peak of BOZ appeared at 218℃, B and oxazine ring were combined by B--O--C, and the highest the boric content in BAE-BOZ was 8.67%, the initial pyrolysis temperature was about 302℃, and the carbon residual at 800℃ increased from 41.80% to 58.08%. The thermal decomposition temperature of BAE-BOZ/E-51 copolymer reached 343 ℃.