含双DOPO的双酚A-单苯并(口恶)嗪合成、表征及其与环氧树脂共聚物的阻燃性能

以含双DOPO-双酚A、苯胺和多聚甲醛为原料,合成了含双DOPO的双酚A-单苯并(口恶)嗪(1DD)。采用红外、核磁(氢谱核磁和碳谱核磁)等分析手段对1DD的化学结构进行了表征;采用DSC对1DD的固化特性进行研究,使用TG分析了所得聚苯并(口恶)嗪的热稳定性。再将1DD与环氧树脂以0.5/1的质量比进行共混,按照一定的程序进行升温固化,得到共聚物P1DD-ER。采用UL94垂直燃烧实验、极限氧指数仪(LOI)测试了共聚物的阻燃性能。结果表明:含双DOPO的双酚A-单苯并(口恶)嗪树脂的起始熔点约为185℃,在222℃处有一个很明显的放热峰。固化后的树脂从348℃开始分解,在463℃分解速率达到最快,在800℃时的残碳率为35.78%。制备的苯并(口恶)嗪可以用作环氧树脂的固化剂,且其共聚物具有很好的阻燃性能,LOI可以达到37,UL94等级为V-0。

Synthesis,characterization of single benzoxazine contained bis-DOPO based on bisphenol A and flame retardant performance of its copolymer with epoxy

Single benzoxazine contained bis DOPO based on bisphenol A (1DD) was synthesized from bisphenol A contained double DOPO (2DO), aniline and paraformaldehyde. FTIR, NMR(¹H NMR,¹³C NMR) were used to characterize chemical structure of 1DD. Curing characteristics were studied with DSC and thermostability was studied with TG. The product was blended with epoxy resin with mass ratio 0.5/1 according to a specific procedure for heat curing to prepare copolymer P1DD-ER. Flame retardant properties of the copolymer was investigated with the UL94 vertical burning test and limit oxygen index (LOI). Starting melting point of 1DD was nearly 185℃. An obvious exothermic peak was observeed at 222℃. Initial decomposition temperature of the copolymer after curing was 348℃. The fastest speed of decomposition was recorded at 463℃. Carbon residue at 800℃ was 35.78%. The prepared benzoxazine could be used as the curing agent of epoxy resin. The copolymer had good flame retardant performance. LOI could reach 37. The grade of UL94 was V-0.