摘要
为了大幅度提高聚醋酸乙烯酯的耐水性,本文采用全氟烷基乙基丙烯酸酯单体(FA)对其进行改性,并通过羟甲基丙烯酰胺(HMA)进行内交联,以醋酸乙烯酯(VAc)、丙烯酸(AA)、丙烯酸丁酯(BA)为主要单体,以聚乙烯醇(PVA)为保护胶体,通过无皂乳液聚合法制备了全氟内交联型聚醋酸乙烯酯乳液。同时考察了全氟单体和交联剂用量比对乳液粒径、流变性和涂膜耐水性的影响,并确定了它们的最适宜条件。研究结果表明,乳液为非牛顿流体,且具有一定的假塑性和触变性,表观黏度随切变速率的变化规律呈现切力变稀特征,当全氟单体用量为6%和交联剂用量为2.5%时,全氟内交联型聚醋酸乙烯酯膜具有良好的稳定性和耐水性。
In order to substantially improve the water resistance of polyvinyl acetate, perfluoro internal crosslinking polyvinyl acetate emulsion was prepared by the emulsifier-free copolymerization with vinyl acetate （VAc）, butylacrylate （BA） and acrylic acid （AA） using perfluoroalkylethyl acrylate （FA） as modified monomer and hydroxymethyl acrylamide （HM）as inter-crosslinking agent and polyvinyl alcohol （PVA） as protective colloid. The influences of the content of perfluorinated monomer and crosslinking agent on particle diameter, Rheological behaviors, and the water resistance of the casting films ,were investigated. The results show that the emulsions exhibit a Non-newtonian behavior, and they are endowed with pseudoplasticity and thixotropy. It is noticed that the apparent viscosity decreases with increasing the shear rate, that is, the emulsions show a characteristic of shear thinning. When the dosage of perfluorinated monomer and crosslinking agent respectively are 6% and 2.5%, the modified polyvinyl acetate membrane has good stability and water resistance.
出处
《胶体与聚合物》
2009年第4期1-5,共5页
Chinese Journal of Colloid & Polymer
基金
国家自然科学基金项目(50673055)
陕西省自然科学基金项目(2007E118)
关键词
聚醋酸乙烯酯
全氟
内交联
流变性
耐水性
Polyvinyl acetate
Perfluorine
Intercross-linking
Rheological behaviors
Water resistance
