改性埃洛石纳米管在聚脲基防火涂料中的应用研究

Study on application of modified halloysite nanotubes in polyurea⁃based fireproof coatings

为了提高聚脲基防火涂料的防火性能,探究埃洛石纳米管对聚脲基涂料防火性能的影响,通过表面改性的方法,用甲基三甲氧基硅烷改性埃洛石纳米管,并将改性埃洛石纳米管引入到聚脲膨胀型防火涂料中,采用锥形量热仪、红外光谱分析仪、导热系数仪、场发射扫描电镜、透射扫描电镜、防火性能测试装置等对其进行表征分析。研究发现:添加质量分数为5%的改性埃洛石纳米管的涂料样品的热释放峰值为95.89 kW/m^(2),相较未添加的样品降低了38.48%;总的热释放量为7.20 MJ/m^(2),相较未添加的样品降低了76.50%;总的烟释放值为4.32 m^(2),相较未添加的样品降低了40.98%;常温下导热系数为0.067 W/(m·K),相较未添加的样品降低了17.30%;燃烧后样品残留物表面更加致密,强度更高,对烟热的释放有更好的抑制作用,表现出了优异的防火性能。实验结果表明,改性埃洛石纳米管在降低复合材料导热系数和基体树脂催化成炭方面起到了双重作用,对聚脲基防火涂料防火性能的提高起到了重要作用。

To improve the fireproof performance of polyurea‐based fireproof coatings,the effect of elosilicate nanotubes on the fireproof performance of polyurea‐based coatings was investigated.Through the method of surface modification,the hal‐loysite nanotubes were modified with methyltrimethoxysilane,and the modified halloysite nanotubes were introduced into the polyurea intumescent fireproof coatings.The cone calorimeter,infrared spectrum analyzer,thermal conductivity meter,field emission scanning electron microscope,transmission scanning electron microscope,and fire resistance testing device were used to characterize and analyze them.It was found that the peak heat release value of the paint sample with 5%modi‐fied halloysite nanotubes added was 95.89 kW/m^(2),which was 38.48%lower than that of the unadded sample.The total heat release was 7.20 MJ/m^(2),which was 76.50%lower than that of the unadded sample.The total smoke release value was 4.32 m^(2),which was 40.98%lower than that of the unadded sample.The thermal conductivity at room temperature was 0.067 W/(m·K),which was 17.30%lower than the unadded sample.In addition,the surface of the sample residue after combustion was denser and stronger,with better inhibition of the release of smoke and heat,showing excellent fire perfor‐mance.The experimental results showed that the modified elosilicate nanotubes played a dual role in reducing the thermal conductivity of the composites and catalyzing the carbon formation of the matrix resin,which significantly improved the fire resistance of the polyurea‐based fireproof coatings.