Nanocomposites from poly(ethylene- co -methacrylic acid) ionomers: effect of surfactant structure on morphology and properties
Nanocomposites from poly(ethylene- co -methacrylic acid) ionomers: effect of surfactant structure on morphology and properties
复制标题
DOI：
10.1016/j.polymer.2005.01.062
复制
发表时间：
2005-03
期刊：
影响因子：
4.6
通讯作者：
R. K. Shah;D. Hunter;D. R. Paul
中科院分区：
文献类型：
--
作者：
R. K. Shah;D. Hunter;D. R. Paul
详细研究了由聚（乙烯-共-甲基丙烯酸）的钠离聚物和一系列有机粘土通过熔融加工技术制备的纳米复合材料的结构-性能关系。透射电子显微镜，X射线散射，应力-应变行为，和悬臂梁冲击分析被用来评估纳米复合材料的形态和物理性能。四种不同的表面活性剂结构效应导致这些纳米复合材料的剥离水平提高和刚度提高：胺上的烷基尾数较高而不是一个，烷基尾较长而不是较短，使用2-羟乙基而不是铵离子上的甲基，以及粘土上过量的胺表面活性剂而不是等量。这些趋势与在尼龙6基纳米复合材料中所观察到的相反，但与在由LDPE和LLDPE形成的纳米复合材料中观察到的趋势相似。虽然一些有机粘土剥离比别人更好，没有一个基于离聚物的纳米复合材料表现出剥离水平，如尼龙6纳米复合材料中看到的那些大，然而，这些纳米复合材料提供了有前途的性能改进，并可能是特别有趣的屏障应用。
A detailed study of the structure–property relationships for nanocomposites prepared using melt processing techniques from a sodium ionomer of poly(ethylene-co-methacrylic acid) and a series of organoclays is reported. Transmission electron microscopy, X-ray scattering, stress-strain behavior, and Izod impact analysis were used to evaluate the nanocomposite morphology and physical properties. Four distinct surfactant structural effects lead to improved levels of exfoliation and higher stiffness for these nanocomposites: higher number of alkyl tails on the amine rather than one, longer alkyl tails instead of shorter ones, use of 2-hydroxy-ethyl groups as opposed to methyl groups on the ammonium ion, and an excess amount of the amine surfactant on the clay instead of an equivalent amount. These trends are opposite of what has been seen in nylon 6 based nanocomposites but are similar to those observed in nanocomposites formed from LDPE and LLDPE. Although some organoclays were exfoliated better than others, none of the ionomer-based nanocomposites exhibited exfoliation levels as great as those seen in nylon 6 nanocomposites; nevertheless, these nanocomposites offer promising improvements in performance and may be particularly interesting for barrier applications.