通过调整玻璃过渡温度来推进高功能化的基于葡萄糖的聚碳酸盐的开发
Yue Song, Xiaozhou Ji, Mei Dong
1College of Medicine , Texas A&M University , Bryan , Texas 77807 , United States.
Journal of the American Chemical Society
|November 13, 2018
概括
研究人员通过改变侧链来调整天然产品基聚合物的玻璃过渡温度 (Tg). 这种可调性是开发具有多样性热性质的高级葡萄糖基聚碳酸盐的关键.
科学领域:
- 聚合物化学
- 材料科学
- 有机化学
背景情况:
- 基于天然产品的聚合物可用于各种应用.
- 了解影响聚合物特性的因素对于材料设计至关重要.
- 基于葡萄糖的聚合物是一种有前途的可再生材料.
研究的目的:
- 在线性聚糖碳酸盐中研究玻璃过渡温度 (Tg) 的可调性.
- 将Tg变化与侧链结构和摩尔质量相关联.
- 推进可功能化的基于葡萄糖的聚碳酸盐的开发.
主要方法:
- 在控制的聚合度下合成和分离线性多糖碳酸和离散的寡合物.
- 系统地改变基碳酸侧链以修改聚合物结构.
- 在一系列合成的聚合物中测量玻璃过渡温度 (Tg).
主要成果:
- 通过修改六种不同的基碳酸侧链,实现了从38°C到125°C的广泛Tg值.
- 证明Tg受到侧链灵活性,体积和链末自由体积的协同作用的显著影响.
- 确定了聚合物结构 (侧链和摩尔质量) 和热性质之间的明确关系.
结论:
- 侧链工程提供了一个强大的策略来调整基于葡萄糖的聚碳酸的热性能.
- 这些发现使得基于葡萄糖的聚合物能够在特定的应用中具有特定的玻璃过渡温度.
- 这项研究突出了简单的侧链修饰的潜力,以创造具有多样化的物理化学和热特性的材料.
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