丁二烯/苯乙烯/4-乙烯基吡啶共聚物蒙脱土嵌入混杂材料的研究

用聚合物乳液与蒙脱土的水分散体共混共凝的方法制备混杂材料.在混合过程中乳胶粒与蒙脱土晶层相互穿插,用盐酸絮凝,带正电的共聚物能够嵌入带负电的蒙脱土层间.萃取实验发现在混杂材料中蒙脱土吸附了大量的共聚物,说明蒙脱土晶层与共聚物之间存在静电吸附作用.XRD实验发现在混杂材料中蒙脱土的晶层结构发生了膨胀,并且变得混乱,而在共混物中蒙脱土晶层结构几乎不变.用TEM观察在混杂材料中蒙脱土晶层均匀分散于共聚物基体中,蒙脱土的层间距大于6nm.共聚物嵌入蒙脱土的层间,受到蒙脱土晶层的限制作用,共聚物的T_g发生了变化.交联以后的混杂材料的性能比共聚物有了较大的提高,蒙脱土晶层在共聚物基体中起到很好的补强作用.

Studies on Butadiene/Styrene/4-Vinyl Pyridine Copolymer-montmorillonite Intercalated Hybrid

Anew method to prepare polymer-montmorillonite hybrid was developed. Montmorillonite could be dispersed in water as exfoliated layers, then when it was blended with the butadiene/styrene/4-vinyl pyridine copolymer emulsion, the latex particle was interpenetrated with the layer of montmorillonite during the blending process. When the blend was coagulated by hydrochloric acid, the pyridine group reacted with H⁺, so the copolymer with positive charge could intercalate the layer of montmorillonite that had negative charge. There was some strong bonding between copolymer and montmorillonite in the hybrid. The extracting experiment showed that montmorillonite absorbed some copolymer. It was found that the layer structure of montmorillonite was swollen and became chaos by means of XRD. TEMshowed that the layer dispersed uniformly in the copolymer matrix and the distance between the layers was more than 6 nm. Copolymer molecule intercalated montmorillonite layer, so it's motion was confined by the layers. DSCshowed that the T_g of copolymer in hybrid had been changed. The mechanical properties of hybrid had been improved greatly after it was vulcanized, the layer could act as a good reinforcing agent for the composites.