旋转交叉树枝状体:对于热旋转过渡的代数依赖的合作性
Tsuyohiko Fujigaya1, Dong-Lin Jiang, Takuzo Aida
1Department of Chemistry and Biotechnology, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
Journal of the American Chemical Society
|April 14, 2005
概括
带有三醇单元的树突协调聚合物表现出热旋转过渡. 增加树突生成数量降低了聚合和过渡温度,但旋转过渡的突然性有所不同,G1trzFe显示了最明显的变化.
科学领域:
- 协调聚合物化学 聚合物化学
- 材料科学是一种材料科学.
- 超分子化学 超分子化学
背景情况:
- 合成了具有焦点三醇单元的聚乙烯 (聚乙烯) 树枝.
- 铁 (II) 复合物与这些树突形成树突协调聚合物.
- 这些聚合物表现出热旋转过渡.
研究的目的:
- 为了研究树突生成数对树突协调聚合物的旋转过渡性质的影响.
- 描述这些新型材料的结构和热行为.
主要方法:
- 聚乙) 树枝与三醇单位 (Gntrz,n=0-2) 的合成.
- 与 (MeSO3) 2Fe 的反应形成树突协调聚合物 ([Fe(Gntrz) 3) ((MeSO3) 2.2H2O).
- 使用热量计和X射线衍射分析热旋转过渡的分析.
主要成果:
- 旋转交叉温度 (Tc) 随着树突生成的增加而下降 (n=0:335 K,n=1:315 K,n=2:300 K).
- 聚合物的平均程度随着生成的增加而下降 (n=0:20,n=1:10,n=2:3).
- 旋转过渡的突然性有所不同:G1trzFe显示宽度窄 (10K),而G0trzFe (30K) 和G2trzFe (50K) 的过渡更宽.
- X射线衍射和热量计揭示了盘状柱状核心外组件.
结论:
- 树突单元的生成数影响着旋转过渡温度和协调聚合物中的聚合度.
- 旋转过渡的突然性不仅仅取决于代数.
- 树突协调聚合物形成有序的超分子结构,在材料科学中具有潜在的应用.
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