关键词: 阳离子水性聚氨酯, 聚合工艺, 热性能

Abstract: Water-borne cationic polyurethanes were synthesized by five polyesters and polyethers glycol, four diisocyanates and hydrophilic chain-extender, N-methyl diethanol amine, with different polymerization processes. The results showed that the addition polymerization process of the introduction of the diisocyanate into the mixture of polyol and hydrophilic chain-extender was appropriate, and the stable water-borne cationic polyurethane was prepared. The properties of cationic polyurethane emulsions and their films dispersed at 35℃ were better than that at 70℃. Especially, the tensile strength of the sample could be increased much more 3 times when the cationomer was dispersed in 35℃. The research results on the content of hydrophilic chain-extender and hard segment in cationic polyurethane indicated that the particle size of cationic polyurethane latex was decreased and the stability of the latex was augmented with increase of the addition of the hydrophilic chain-extender when the content of hard segment got to 30%(w) upwards, and the tensile strength of the cationic polyurethane film was also increased. The thermal analysis of the cationic polyurethane elucidated that the ordered structures of the hard and soft segments in the cationic polyurethane film were destroyed when the content of hard segment reached up to 40%(w), and that the glass transition temperature of the cationic polyurethane film was more than 15℃.

Key words: water-borne cationic polyurethane, polymerization process, thermal property