染聚胺胺) 或聚烯胺) 树状体,对温度敏感.
Yasuhiro Haba1, Atsushi Harada, Toru Takagishi
1Department of Applied Materials Science, Graduate School of Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Sakai, Osaka 599-8531, Japan.
Journal of the American Chemical Society
|October 8, 2004
概括
研究人员合成了以异黄胺末端的多胺胺) 树突. 高一代树枝状体显示较低的临界溶液温度,表明高效的温度敏感性质.
科学领域:
- 聚合物化学 聚合物化学
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
背景情况:
- 聚胺胺) 树枝体是有分支的宏分子,具有多样化的应用.
- 开发响应刺激的材料对于先进的应用至关重要.
- 通过表面修饰来控制树突体的特性是一个活跃的研究领域.
研究的目的:
- 为了合成异布胺 (IBAM) 终结的多胺胺) dendrimers.
- 研究IBAM群密度对树枝状分子特性的影响,特别是温度灵敏度.
- 评估IBAM功能化在制造温度敏感聚合物的潜力.
主要方法:
- 使用异黄油酸和1,3-二环基碳二胺胺基,合成IBAM终结的多胺基 (G2-G5) 树突体.
- 使用核磁共振 (NMR) 光谱 (1H和13C) 进行表征,以确认IBAM组的附着.
- 通过观察溶解度与温度的变化来确定较低的临界溶液温度 (LCST).
主要成果:
- 成功地将IBAM组连接到跨代G2到G5.5的多胺胺) 树突的末端.
- 终结IBAM的G2树脂分子仍然在水中溶解.
- 终结IBAM的G3,G4和G5树枝体呈现出分别75°C,61°C和43°C的LCST下降.
- 随着更高的一代的IBAM群密度的逐渐增加与LCST的显著下降相关.
结论:
- 终端IBAM组的密度直接影响了多胺胺) 树状体的较低临界溶液温度 (LCST).
- 增加代数导致IBAM群体密度更高,温度敏感行为更强.
- 使用IBAM组的功能化是一种有效的策略,用于传递对树枝状体的温度敏感性,包括聚烯胺树枝状体.
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