晶体结构和7,7,8,8-tetrakis ((alkoxycarbonyl) quinodimethanes的高化学聚合物
Shinji Nomura1, Takahito Itoh, Hirofumi Nakasho
1Department of Chemistry for Materials, Faculty of Engineering, Mie University, 1515 Kamihama-cho, Tsu-shi, Mie 514-8507, Japan.
Journal of the American Chemical Society
|February 20, 2004
概括
多态二甲单体在固态中表现出明显的聚合行为,受晶体包装的影响. 这项研究探讨了分子排列如何影响拓化学和热聚合的结果.
科学领域:
- 材料科学 材料科学 材料科学
- 聚合物化学 聚合物化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 合成了高度结合的单体,特别是7,7,8,8-四基{alkoxycarbonyl) 二甲基.
- 在几种合成的二甲衍生物中观察到多态性,不同的晶体形式表现出不同的分子包装安排.
研究的目的:
- 为了研究多态二甲单体的固态聚合行为.
- 为了将分子包装参数与聚合反应性和聚合物形态 (晶体与无形) 相关联.
主要方法:
- 合成了一系列的7,7,8,8-tetrakis ((alkoxycarbonyl) 二甲单体.
- 进行X射线晶体结构分析以确定分子包装模式和识别多态形式.
- 固态光聚合和热聚合实验.
- 分析晶体包装参数,包括堆叠距离,碳之间的距离和角方向.
主要成果:
- 特定的多态形式 (1a-A,1e-A,1f-A) 经过了高化学光聚合,产生了晶体聚合物.
- 热聚合发生在晶体 (1a-A,1e-A,1f-A) 和某些无形 (1e-B,1f-B) 形式中.
- 从无形前体 (1e-B,1f-B) 衍生出的聚合物本身是无形的.
结论:
- 二甲晶体中的分子包装安排显著影响其固态聚合活性和由此产生的聚合物结构.
- 关键的包装参数 (堆叠距离,碳之间的距离和方向角) 对于预测聚合结果至关重要.
相关概念视频
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