阳离子聚氨酯/丙烯酸酯分散液的流变性能及胶膜力学性能  

Rheology of Cationic Polyurethane/crylate Dispersions and Mechanical Properties of Films

作　　者：王海花[1] 兰静[1] 费贵强 姜春阳[1] 

机构地区：[1]教育部轻化工助剂化学与技术重点实验室陕西科技大学,陕西西安710021

出　　处：《材料科学与工程学报》2015年第5期736-742,共7页Journal of Materials Science and Engineering

基　　金：国家自然科学基金资助项目(21204046;51373091);陕西省中国科学技术研究发展计划资助项目(2013KJXX-77);陕西省教育厅重点实验室资助项目(13JS018)

摘　　要：通过引入三羟甲基丙烷(TMP)交联剂和丙烯酸羟乙酯(HEA)偶联剂,采用种子乳液聚合法制备了系列阳离子聚氨酯-聚丙烯酸酯(PUA)分散液。系统分析了TMP和HEA用量对分散液粒径、流变行为以及胶膜力学性能的影响。单独引入TMP,分散液粒径增加,储能模量增加,损耗模量减小,相容性增加,胶膜的断裂强度增加,断裂伸长率下降;但过量的TMP会导致损耗模量和弹性急剧增加,分散液出现相分离行为,稳定性下降。单独引入适量HEA,分散液粒径减小,分散液由粘性向粘弹性行为转变,同时由牛顿流体转变为假塑性流体,乳胶粒间相互作用增强,分散液呈现反触变性。同时引入TMP和HEA,固定TMP用量为0.4%,随着HEA用量的增加,分散液从正触变性转变为复合触变性,黏度增加,乳胶粒间的相互作用增加,假塑性和触变性增强,胶膜的力学性能得到明显改善。A series of cationic polyurethane-polyacrylate（PUA）dispersions was obtained through seed emulsion polymerization,using trimethylolpropane（TMP）as cross-linker and hydroxyethyl acrylate（HEA）as coupling agent to connect polyurethane（PU）and polyacrylate（PA）.Effects of TMP content and HEA content on the particle size and rheological behavior of the PUA dispersions were systematically investigated,and the mechanical properties influenced by TMA and HEA of the PUA films were also studied.When TMP is solely introduced into PUA system,the particle size and storage modulus of dispersion increase and loss modulus decreases with increasing TMP content.Compatibility and breaking stress of the film also increase,but breaking elongation decreases.However,excessive TMP causes great increase in loss modulus and elasticity;phase separation behavior thereby takes place in PUA dispersions,leading to a decrease in stability.When HEA is introduced into the PUA system independently,the particle size decrease with increasing HEA content,the dispersion transforms from viscous to viscoelastic state,and simultaneously changes from Newtonian fluid to pseudoplastic fluid.Interactions between PUA colloidal particles are also enhanced and dispersions are demonstrated to be anti-thixotropic liquid.When TMP and HEA are both introduced into PUA system by fixing TMP content at 0.4%,the dispersion transforms from positive thixotropic liquid to complex thixotropic liquid with increasing HEA content.Viscosity and interaction between colloidal particles alsoincreased with increasing HEA content,as well as the pseudoplasticity and thixotropy of dispersions.Meanwhile the mechanical properties of the films are significantly improved.

关 键 词：阳离子 聚氨酯-聚丙烯酸酯 流变性 力学性能 相互作用 

分 类 号：TQ633.3[化学工程—精细化工]