Aimed at increasing the hydrophobicity of cathodic electrodeposition (CED) coatings based on cationic waterborne polyurethanes (WPUs), a series of cationic WPUs with hydrophobic octadecyl side chains were successfully synthesized by introducing 1-monostearoyl-rac-glycerol as a diol chain extender. ATR-FTIR spectra and SEM images showed the degree of phase separation between soft segments and hard segments of cationic WPUs clearly increased by incorporating octadecyl groups. The water contact angle and water absorption studies showed that the water-resistance property of modified CED coatings was obviously enhanced because of the incorporation of a low surface energy unit and the formation of a more sophisticated surface induced by hydrogen bonds. The International Standardization test of paints and varnishes revealed that the CED films possessed excellent hardness, adhesion, flexibility, and impact resistance. Optical transmittance tests showed that the sample films possessed excellent optical transmittance of about 90%, and meanwhile, the thermostability of the film was promoted.

旨在提高基于阳离子水性聚氨酯（WPU）的阴极电沉积（CED）涂料的疏水性，通过引入1-单硬脂酰基-rac-甘油作为二醇扩链剂，成功合成了一系列具有疏水性十八烷基侧链的阳离子WPU。ATR-FTIR光谱和SEM图像显示，通过结合十八烷基，阳离子WPU的软链段和硬链段之间的相分离程度明显增加。水接触角和吸水率研究表明，改性CED涂层的耐水性明显提高，这归因于低表面能单元的引入和氢键的诱导形成了更复杂的表面。油漆和清漆的国际标准化测试表明，CED膜具有出色的硬度，附着力，柔韧性和抗冲击性。透光率测试表明样品薄膜具有约90％的优异透光率，同时，提高了薄膜的热稳定性。