功能单体对苯乙烯-丙烯酸丁酯乳液共聚物黏弹性能的调控作用  

Regulation of Viscoelastic Properties of Styrene-Butyl Acrylate Copolymer by Functional Monomer

作　　者：李保文[1] 管爱国[1] 徐成[1] 兰方兴 吴国章[1] 

机构地区：[1]华东理工大学材料科学与工程学院,上海市先进聚合物材料重点实验室,上海200237

出　　处：《华东理工大学学报（自然科学版）》2014年第1期41-46,共6页Journal of East China University of Science and Technology

基　　金：国家自然科学基金(20974033)

摘　　要：在苯乙烯-丙烯酸丁酯乳液聚合中,加入少量功能单体甲基丙烯酸(MAA)和甲基丙烯酸羟乙酯(HEMA)(两者的质量分数小于6.0%)参与共聚,采用差示扫描量热仪(DSC)、动态机械分析仪(DMA)以及旋转流变仪对聚合物的黏弹行为进行研究,并分析了聚合物黏弹行为变化的机理。结果表明:随着功能单体用量增加,聚合物的玻璃化温度、储能模量、黏度等整体呈上升趋势,当m(MAA)∶m(HEMA)为0.5∶4.1以及1.2∶2.5时,黏弹行为变化显著。凝胶渗透色谱(GPC)结果表明,黏弹行为变化的主要因素并非由聚合物相对分子质量及其分布变化引起。通过2组聚合物在乙酸乙酯中的溶解实验,发现了凝胶现象,FT-IR图谱证明此凝胶是由不同类型的氢键作用引起的,这也是导致聚合物黏弹性急剧变化的主要原因。Using a small amount of methacrylic acid （MAA） and hydroxyethyl methac as functional monomers （total mass fraction less than 6.0%） in styrene-butyl ac eopolymerization, the viscoelastic behavior of the copolymer and the mechanism of change ry ry ate （HEMA） ate emulsion were studied by means of DSC, DMA and rheology. Results showed that the glass transition temperature, the storage modulus, viscosity of the polymer increased with the increasing of dose of functional monomers, and the viscoelastic behavior changed significantly when m（MAA） ： m（HEMA） are 0.5 ： 4.1 and 1.2 ：2.5. GPC tests showed that the change of the viscoelastic behavior was not caused mainly by the molecular weight and distribution. Gelling was found by dissolving copolymers with this two proportions in ethyl acetate. FT-IR results demonstrated that the gelling was originated from different types of hydrogen bonding, and was also the main reason leading to the viscoelastic behavior change.

关 键 词：乳液聚合 功能单体 黏弹性 凝胶 

分 类 号：O632[理学—高分子化学]