【作者】 马景松；

【导师】 李再峰；

【作者基本信息】 青岛科技大学 ， 物理化学， 2007， 硕士

【摘要】 本论文对水性聚氨酯体系和改性水性聚氨酯树脂进行了深入的研究，论文主要包括以下4部分内容：第一部分系统地研究了水性阳离子型聚氨酯树脂的制备。论文讨论了亲水性扩链剂MDEA的含量、异氰酸酯种类、低聚物多元醇种类和软硬段比例等对聚氨酯及其电泳漆性能的影响；制备出双组分阴极聚氨酯电泳漆并研究其性能。研究结果表明MDEA含量决定乳液的稳定性和的外观；以脂环族异氰酸酯、聚酯多元醇为原料制备的水性聚氨酯电泳漆膜性能较好；双组分阴极电泳漆的耐腐蚀性能比单组分好。第二部分以自由基聚合方法制备出阳离子型羟基丙烯酸树脂，以甲苯二异氰酸酯(TDI)和丁酮肟(MEKO)合成出半封端型TDI，将两种产物混合反应，制备出系列聚氨酯改性的丙烯酸树脂乳液。乳液成膜后，在高温下解封的NCO官能团同丙烯酸树脂上的羟基反应得到异氰酸酯交联丙烯酸树脂膜。实验结果表明随交联度提高，交联丙烯酸树脂的Tg和材料的凝胶含量增加、材料的拉伸强度、硬度、耐腐蚀性、吸水率同时得到提高。第三部分研究了光固化聚氨酯树脂。以丙烯酸羟乙酯(HEA)封端-NCO制备了光固化阳离子型聚氨酯乳液，讨论了HEA封端比例对乳液性能的影响；研究了固化后树脂的玻璃化转变温度、力学性能和耐腐蚀性能。研究结果显示HEA封端比例增大，乳液稳定性下降；随封端比的增大树脂的Tg升高、耐溶剂性增强、硬度和拉伸强度性能增大、耐腐蚀性能也得到提高。第四部分采用环氧树脂嵌段改性了聚氨酯阳极电泳漆。测试结果显示：高温固化后电泳漆膜的丰满度、厚度、耐腐蚀性都随环氧树脂含量增大而得到改善；环氧E-12的改性效果优于环氧E-44；电泳漆膜的丰满度随改性后聚氨酯的中和度降低而得到改善，漆膜厚度也相应增加，乳液稳定性变差。当中和度为80％时，电泳漆膜的外观和综合性能较好。更多还原

【Abstract】 In this dissertation, the synthesis and modification of water-based polyurethaneresins and their properties were studied. The dissertation consists of four main parts asfollow:The first part, the preparation of water-based cationic polyurethane and itsdispersion were studied. The effect of process variables such as contents of MDEA,diisocyanates, polyols, initial NCO/OH(R index) on the performance of water-basedpolyurethane resin and the electrophoretic film was discussed. The results showed thatthe particle size and storage stability of PU dispersion were determined by the contentof MDEA, the hardness of film became harden with an increasing in R (NCO/OH)index, the performance of electrophoretic film synthesized by IPDI and polyester wasbetter than that of PU dispersion from the other raw material.The second part, the properties of semi-blocked TDI grafted cationic acrylic resinwere studied. Hydric-acrylic resin was synthesized by free radical copolymerization,and then the acrylic resins modified by PU were prepared from the hydric-acrylicresin and semi-blocked TDI by MEKO. Isocyanate cross-linking cationic acrylicresins was carried out by the reaction of the NCO group of TDI with the hydroxylgroup of the hydric-acrylic resin at high temperature. The results showed that with anincrease in the crosslinked density, the Tg and gel-content increased gradually. Thecorrosion resistance, water-proof capability and the mechanic properties were alsoimproved.The third part, UV curing water-based polyurethane resin was synthesized. The resinwas prepared from the reaction of the NCO group of PU prepolymer with OH groupof HEA compound. The properties of the UV cured resin were studied. The resultsshowed that with an increase in the content of blocking agent (HEA), the Tg, hardnessand gel-content of the cured PU resin increased gradually, whereas both emulsion dispersibility and storage stability became worse. The acid or alkali resistance,water-proof ability and the mechanic properties were all improved much.The fourth part, in order to improve the poor corrosion resistance ability andincrease the thickness of electrophoretic film, the epoxy resin was employed tomodify the molecule chain of polyurethane resin. The satisfied electrophoretic filmswere obtained and the performance of the film were improved much. The modifiedresult of E-12 was superior to that of E-44, and when the neutralization degree of themodified PU resin was about 80％, the film from the PU dispersion was desired.更多还原