不同软硬度比值下酮肼交联聚氨酯丙烯酸酯材料的原位聚合与性能
2017-10-17费贵强杨小芳王海花姜春阳
费贵强, 杨小芳, 王海花, 姜春阳
(陕西科技大学 教育部轻化工助剂化学与技术重点实验室, 陕西 西安 710021)
不同软硬度比值下酮肼交联聚氨酯丙烯酸酯材料的原位聚合与性能
费贵强, 杨小芳, 王海花, 姜春阳
(陕西科技大学 教育部轻化工助剂化学与技术重点实验室, 陕西 西安 710021)
通过原位聚合方法制备酮肼交联聚氨酯丙烯酸酯复合乳液,探讨了不同NCO/OH比值(R值)、不同MMA/BA比值对聚氨酯丙烯酸酯材料性能的影响.通过红外光谱、热失重分析仪等对其进行表征.随着R值提高,乳液黏度、粒径均增大,胶膜的耐水性、热稳定性、交联密度及力学性能得到提高;MMA/BA比值从0增加至8,涂层的附着力、硬度逐步提高,乳液粒径逐渐增大,乳液粘度和胶膜吸水率均先减小再增大.
聚氨酯丙烯酸酯; 酮肼交联;R值; 软硬度
Abstract:Keto-hydrazine crosslinked polyurethane acrylate emulsion was prepared through in-situ polymerization method.Effects of NCO/OH ratio (Rvalue),MMA/BA ratio on the properties of polyurethane acrylate material were studied.Meanwhile,the structure was characterized via infrared spectrum,thermogravimetric analysis and so on.With increasing theRvalue,emulsion viscosity and particle size were increased,as well as the water resistance,thermal stability,crosslinking density and mechanical properties.As the MMA/BA ratio increases,the adhesion and hardness of coating gradually increased,the storage stability and particle size of the emulsion also increases gradually.The emulsion viscosity and water absorption of film decreased firstly and then increased.
Keywords:polyurethane/polyacrylate; ketone hydrazine crosslinking;Rvalue; soft-hard
0 引言
水性聚氨酯具有耐低温、柔韧性好、附着力强等优点,但胶膜的耐水性较差、硬度较低、乳液的稳定性也较差.聚丙烯酸酯具有机械强度高、耐老化、耐光不变黄、耐水性好等优点,但存在着耐有机溶剂性、坚韧性、耐磨性、耐化学品差及高温发粘、低温发脆等缺点.因此,将聚氨酯和聚丙烯酸酯通过两者复合,可以取长补短,发挥综合优势,使涂膜的性能得到明显改善,因而具有广阔的发展前景[1,2].近年来,有关聚氨酯-丙烯酸酯(PUA)复合乳液的研究比比皆是[3-8].
酮肼交联反应原理为通过酮羰基和肼及其衍生物发生缩合反应生成腙从而使聚合物发生交联.室温条件……
