【摘要】 传统的自乳化型羧酸类水性聚氨酯乳液对电解质溶液非常敏感,制约了其在涂料、油墨等领域的应用。为提高聚氨酯乳液的电解质稳定性,本研究使用一定量的具有聚氧乙烯基醚结构的亲水单体Ymer N120,部分取代羧酸型亲水单体二羟甲基丁酸(DMBA),通过调节DMBA与YmerN120的质量比,制备了系列阴/非离子型水性聚氨酯(WYPU),研究了Ymer N120/DMBA质量比对乳液及其水性油墨性能的影响。研究结果表明:Ymer N120/DMBA比值的增大,提高了WYPU胶膜的柔顺性,降低了其玻璃化转变温度(Tg),以及乳液的极性和内聚能,因而提高了WYPU在双向拉伸聚丙烯(BOPP)薄膜表面的附着力。同时Ymer N120的助乳化作用赋予乳液良好的高温稳定性和优异的Ca2+稳定性:当Ymer N120用量12%(质量分数),Ymer N120/DMBA质量比为12∶2时,制备得到的WYPU的Ca2+稳定性高达5%,其相应水性油墨在BOPP薄膜上的附着牢度达到90%,剥离强度达到0.64N/15mm,具有较好的应用前景。更多还原

【Abstract】 Traditional carboxylic acid-based waterborne polyurethane latexes are quite sensitive to electrolyte solutions, limiting their applications in coatings, inks and other fields. In this study, in order to improve the electrolyte stability of WPU latexes, a series of anionic/non-ionic waterborne polyurethanes(WYPU) were prepared by using a certain amount of hydrophilic monomer Ymer N120 which contained polyoxyethylene ether structure to replace partially the DMBA(Dimethylolbutyric acid). The effect of the Ymer N120/DMBA ratios on the properties of latexes and the corresponding inks were studied. It was found that increasing the Ymer N120/DMBA ratio is beneficial to improvement of the flexibility of WYPU films and reduction of their Tg. And the adhesion fastness of WYPU ink on BOPP film surface is improved due to increase of the polarity and the cohesive energy of the latexes. In addition, Ymer N120 endows the WYPU latexes with good high temperature stability and outstanding Ca2+ stability owing to its good co-emulsifying effect. When the dosage of the Ymer N120 is 12 wt% and the Ymer N120/DMBA ratio is 12∶2, Ca2+ stability of the WYPU latex as-prepared is as high as 5%, and adhesion fastness and T-peel strength of the corresponding water-based ink on BOPP films reache 90% and 0.64 N/15 mm, respectively, indicating its good application prospect.更多还原