摘要： 为提高涂层防火性能和耐龟裂性能，将埃洛石纳米管（HNTs）与磷酸酯（PRA）分子接枝，再与水性氨基树脂（MF）复配制备透明膨胀型防火涂料。通过傅立叶变换红外光谱、核磁氢谱、X 射线晶体衍射等手段分析了反应机制。利用热重分析、扫描电子显微镜、锥形量热仪等探究埃洛石纳米管对涂层膨胀以及炭层形貌的作用机制。结果表明：HNTs可以通过 Al—OH与 PRA上的 P—OH反应接枝到 PRA 分子链上，同时 PRA 分子还可以插入到 HNTs 的层间，接枝后的 HNTs 对涂层透明性无不良影响；与未添加 HNTs 的涂层相比，当 HNTs 添加量为 5% 时，800 ℃残炭率增大了 42. 2%，引燃时间延长了38 s，AveHRR180 s和THR300 s分别降低了66. 1%和55. 6%，涂层无裂纹产生。

关键词: 防火涂料, 透明, 膨胀炭层, 埃洛石纳米管, 耐龟裂, 磷酸酯, 水性氨基树脂

Abstract: In order to improve the flame retardancy and crack resistance of coating, halloysite nanotubes (HNTs) were grafted with phosphorus-containing reactive agent (PRA) and then combined with waterborne amino resin (MF) to prepare transparent intumescent fire retardant coatings. The reaction mechanism was analyzed by Fourier transform infrared spectroscopy, nuclear magnetic resonance (¹H NMR), X-ray crystallography and other analytical means. Thermogravimetric analysis, scanning electron microscope, and the cone calorimeter were used to explore the action mechanism of the halloysite nanotubes (HNTs) on coating expansion and carbon layer morphology. The results showed that HNTs could be grafted onto the PRA molecule chain through the reaction between Al—OH and P—OH, and PRA molecules could also penetrate the interlayers of HNTs. The grafting of HNTs did not have an adverse effect on the transparency of the coating. When the HNTs content was 5%, the residual char ratio at 800 ℃ increased by 43. 6%. The ignition time, AveHRR180 s, and THR300 s of wood with these coatings with 5%HNTs were extended by 38 seconds, and decreased by 66. 1% and 55. 6%, respectively. And no cracks generated in the coating.

Key words: fire retardant coatings, transparency, intumescent, HNTs, crack resistance, phosphorus-containing reactive agent, waterborne amino resin

中图分类号: 

• TQ637.6