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通过可聚合的双胞胎双胞胎双胞胎双胞胎的交叉连接正常的六角形和双连续立方组件
Brad A Pindzola1, Jizhu Jin, Douglas L Gin
1Department of Chemistry, University of California, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|March 6, 2003
概括
研究人员开发了新的可聚合双子星表面活性剂,形成稳定的液晶相. 这些本质上可以交叉连接的两动物在光交叉连接后保持其结构,提供增强的热稳定性.
科学领域:
- 材料科学 材料科学 材料科学
- 超分子化学 超分子化学
- 聚合物化学 聚合物化学
背景情况:
- 双子座表面活性剂由于它们的双重疏水尾巴和水友头提供了独特的特性.
- 热液晶 (LLC) 阶段是由溶液中的两生物形成的有序结构.
- 交叉连接的两动物可以增强其中相的稳定性和特性.
研究的目的:
- 合成和表征内在可交叉链接的双子表面活性剂.
- 为了研究这些新型两动物的热液晶相行为.
- 探索这些表面活性剂的光交联和由此产生的材料的稳定性.
主要方法:
- 合成基于二甲基 (甲基-1,3-二烯) 的二双双两.
- 在水中进行的热液晶相行为研究.
- 使用紫外线-紫外线光谱学对LLC相进行光交联.
- 粉末X射线衍射用于结构分析.
- 交联材料的热稳定性测试.
主要成果:
- 双子座表面活性剂形成了六边形 (H) 阶段,立方形 (Q) 阶段和状 (L) 阶段.
- 照片交叉链接保留了所有观察到的LLC阶段的阶段架构.
- 聚合度范围从23%到71%不等,确保了系统的稳定.
- 交叉连接的相表现出了显著的热稳定性,在空气中高达300°C.
结论:
- 这些代表了第一个可聚合的双子表面活性物和第一个可交叉链接的两性物,在六角和立方二相中聚合.
- 光交叉链接方法有效地稳定了LLC微结构.
- 由此产生的材料对于需要高热稳定性的应用具有显著的潜力.
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