基于原位聚合法水性聚氨酯/MWCNTs杂化电沉积树脂的制备、形态及性能

Preparation,morphology and properties of electrodeposited resin of waterborne polyurethane/MWCNTs hybrid by in situ polymerization

采用超声波辅助反应技术,通过甲苯二异氰酸酯(TDI)改性羟基多壁碳纳米管(MWCNTs),制备出异氰酸酯修饰的活性MWCNTs。采用原位聚合法制备出MWCNTs杂化的水性聚氨酯树脂,与交联剂混合后得到水性聚氨酯电沉积涂料。采用红外光谱(FT-IR)、透射电子显微镜(TEM)、电导率仪等测试方法,研究了MWCNTs用量对水性聚氨酯漆膜外观和性能的影响。结果表明,MWCNTs成功接枝到聚氨酯分子主链上;随着MWCNTs用量的增加,水性聚氨酯漆膜的导电性、光泽度、硬度和耐酸性表现出先增大后降低的规律。当MWCNTs的质量分数为0.75%时,MWCNTs在水性聚氨酯树脂中表现出最好的分散稳定性,漆膜的导电性、光泽度、硬度和耐酸性等性能达到最佳。

With ultrasonic reaction technique,the reactive carbon nanotubes modified by diisocyanate were prepared by the reaction of NCO group of toluene diisocyanate with hydroxyl from MWCNTs.The aqueous MWCNTs hybrid polyurethane resin was prepared by in situ step polymerization.The characteristic functional groups of MWCNTs before and after the modification and MWCNTs/PU electrodeposition resin were determined by FTIR.The morphology of MWCNTs/PU electrodeposition resins were characterized by TEM.The conductivity of the paint film was tested by the conductivity meter,and the influence of carbon nanotube content on the appearance and performance of the polyurethane paint film was investigated.The results showed that with an increase in content of MWCNTs,the conductivity,gloss,hardness,and acid resistance of polyurethane coatings increase first and then decrease.When the mass content of MWCNTs is 0.75 %,the carbon nanotubes showed the better dispersion stability in the water-based polyurethane resin,and the properties of the paint film such as conductivity,gloss,hardness and acid resistance are the desirable.