通过通过四次键异质复合体介导的自我组装形成可混合的高分子聚合物混合物
Taiho Park1, Steven C Zimmerman
1Department of Chemistry, Roger Adams Laboratory, 600 S. Mathews Avenue, University of Illinois, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|August 31, 2006
概括
研究人员使用不混合的聚甲酸 (PBMA) 和聚烯 (PS) 聚合物制成了一种新型的聚合物混合物. 这种超分子网络聚合物形成单相,具有可调节的玻璃过渡温度 (Tg).
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
- 超分子化学 超分子化学
背景情况:
- 不混合的聚合物混合物通常分相,限制了它们的应用.
- 在聚合物混合物中实现分子级混合是具有挑战性的.
- 结合相互作用提供了一条创建有序超分子结构的途径.
研究的目的:
- 开发一种超分子网络聚合物混合物,由不混合的聚甲酸 (PBMA) 和聚烯 (PS) 制成.
- 为了研究单相混合物的形成,使用特定的结识别单元.
- 描述由此产生的聚合物混合物的特性和网络结构.
主要方法:
- 合成PBMA和PS与瓜诺辛 (UG) 和2,7-米多-1,8-纳菲西里丁 (DAN) 分别的识别单元功能化.
- 使用1H NMR光谱对异构复杂性的表征.
- 通过原子力显微镜 (AFM) 和差分扫描热量计 (DSC) 分析混合物形态和热性质.
- 使用粘度测量,尺寸排除色谱 (SEC) 和动态光散射 (DLS) 评估网络结构.
主要成果:
- 通过1H NMR证实了UG和DAN之间排他性的异构复杂性.
- AFM和DSC发现聚合物混合物中没有相位分离,并且只有一个可调的玻璃过渡温度 (Tg).
- 粘度,SEC和DLS数据支持形成一个稳定的超分子网络结构.
- 混合物的Tg可以通过调整聚合物重量比来有效调整.
结论:
- 在不混合的聚合物链之间实现了高忠度,高亲和度的超分子连接.
- 证明了单相,超分子网络聚合物混合物的形成.
- 这种方法提供了一种途径,通过非共价相互作用来创建具有可调节性质的先进聚合物材料.
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