从葡萄糖碳酸盐基单体替代模式和替代物类型的微妙变化中阐明环开放聚合物的实质性差异
Journal of the American Chemical Society
|July 6, 2023
概括
葡萄糖碳酸盐单体上的替代物显著影响环开聚合和聚碳酸盐特性. 乙烯基组产生区域规律的聚合物,而碳酸盐组导致脊柱不规则性,而硫烯基组防止聚合.
科学领域:
- 聚合物化学
- 碳水化合物化学
- 有机合成
背景情况:
- 双循环葡萄糖碳酸盐是可持续聚合物合成的有价值单体.
- 控制聚合和材料特性是开发高级功能材料的关键.
研究的目的:
- 研究五环二环碳酸单体上的不同替代剂如何影响环开聚合 (ROP) 和产生的聚碳酸的热性质.
- 探索有机基催化剂对聚合结果的影响.
- 将单体结构与聚合物特性如区域规律性,骨干连接性和热行为相关联.
主要方法:
- 五个组成的双循环2,3-葡萄糖碳酸盐单体与多种4,6-保护组 (乙,碳酸盐,硫氨酸) 的合成.
- 这些单体的机基催化环开聚合 (ROP).
- 聚合物区域规律性,骨干连接性和分子质量分布的分析.
- 使用热重度分析等技术,研究热性能,包括热稳定性和玻璃过渡温度 (Tg).
主要成果:
- 具有以太替代物的单体不论催化剂产生区域常规聚碳酸.
- 有碳酸保护组的单体经过过碳化,导致不规则的脊柱和广泛的质分布.
- 硫氨基保护的单体没有经过ROP,可能是由于质子酸度.
- 聚碳酸具有很高的热稳定性,其玻璃过渡温度 (Tg) 从39到139°C不等,受侧链体积的影响.
- 对于含有 tert- butyloxycarbonyl (BOC) 保护组的聚碳酸盐,观察到两阶段的热分解.
结论:
- 单体替代剂对ROP的反应性,区域选择性以及由此产生的聚碳酸盐的热性质进行了批判性控制.
- 通过以太保护的葡萄糖碳酸盐对合成明确的,区域常规的聚碳酸盐具有前景.
- 这些发现为设计下一代基于葡萄糖的可持续功能材料提供了基本的见解.
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