聚乙烯乙甲基酸侧链长度对A/B/A-B三元混合物与聚乙烯的刷子胀行为的影响
Caini Zheng1, Bo Zhang2, Frank S Bates2
1Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA. lodge@umn.edu.
Soft matter
|June 7, 2023
概括
这项研究探讨了使用聚烯和聚[烯基醇]甲基乙烯甲基酸的聚合物混合物相位行为,其侧链长度各不相同. 较长的侧链会影响这些复杂的聚合物系统中的混合性和膨胀行为.
科学领域:
- 聚合物科学与工程 聚合物科学与工程
- 材料化学 材料化学
- 软物质物理学 软物质物理学
背景情况:
- 对同聚合物 (A,B) 和双块共聚合物 (A-B) 的三元混合物进行了充分研究,重点关注相位行为和微乳液形成.
- 之前的研究主要利用线性聚合物,在了解聚合物结构对混合阶段行为的影响方面留下了一个空白.
研究的目的:
- 为了研究三元聚合物混合物与不同聚合物架构的自我组装和相位行为.
- 为了确定甲基 (乙烯基醇) 侧链长度对聚乙烯/聚[甲基 (乙烯基醇) 甲基乙烯甲基酸盐]混合物的相变和可混合性的影响.
主要方法:
- 三组三元混合物的合成,包括聚乙烯 (PS) 和聚乙烯基醇甲基甲基酸 (POEGMAn),具有不同的侧链长度 (n).
- 利用小角度X射线散射 (SAXS) 来分析各种组成和温度的相位行为.
主要成果:
- 发现,顺序转变温度 (ODT) 受到oligo ((乙烯基醇)) 侧链的长度的显著影响.
- 增加的侧链长度与同聚合物及其相应块之间的混合性降低相关.
- 观察到一种类似"干刷"的胀行为,这种行为归因于带有较长侧链的混合物中较差的混合能力.
结论:
- 聚合物架构,特别是侧链长度,在决定三元聚合物混合物的相位行为方面发挥着至关重要的作用.
- 这些发现为控制复杂聚合物系统中的可混合性和自我组装提供了洞察力,这与材料设计有关.
- 这项研究强调了侧链长度对块共聚合物混合物的热力学相互作用和形态转换的影响.
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