在DMSO/TMG/CO2可切换溶剂系统中合成的短链 (混合) 纤维素的结构-性质关系
Timo Sehn1, Michael A R Meier1,2
1Institute of Biological and Chemical Systems - Functional Molecular Systems (IBCS-FMS), Karlsruhe Institute of Technology (KIT), 76131 Karlsruhe, Germany.
Biomacromolecules
|October 15, 2023
概括
这项研究介绍了一种使用新型可切换溶剂系统的生物基纤维素的快速微波辅助合成. 这些纤维素的较长侧链增强了疏水性,降低了性,提供了可持续的材料替代品.
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
- 绿色化学 绿色化学
背景情况:
- 越来越多的环境问题需要替代石油基聚合物.
- 纤维素是一种可再生资源,是生物基材料的有希望的原料.
- 开发有效的纤维素衍生物合成方法对于可持续的材料开发至关重要.
研究的目的:
- 开发一种快速和均的微波辅助合成纤维素 (CEs).
- 为了利用一个新的DMSO/TMG/CO2可切换溶剂系统用于CE合成.
- 为了研究不同长度的乙侧链的CE的结构-属性关系.
主要方法:
- 纤维素 (CE) 的微波辅助合成.
- 使用一个可切换的溶剂系统,该系统由DMSO/TMG/CO2.2组成.
- 使用IR,1HNMR,1CNMR和SEC进行合成CE的表征.
主要成果:
- 实现了高分子量CE (59-116 kDa) 与短,混合的乙侧链 (C=2-8) 的合成.
- 通过改变乙侧链长度来证明可调节性质.
- 观察到玻璃过渡温度 (177-204 °C) 和模量 (7.51-13.6 MPa) 在较长的侧链下降.
结论:
- 开发的方法提供了一种快速有效的途径来合成可调节的纤维素.
- 增加的乙侧链长度增强了表面的疏水性 (WCA 65-98°) 并降低了机械刚性.
- 这些生物基纤维素 Ester显示出作为化石基聚合物的可持续替代品的潜力.
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