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在[mTBNH][OAC]离子液中通过转化反应制备热塑性纤维素
Elvira Tarasova1, Nutan Savale1, Illia Krasnou1
1School of Engineering, Department of Materials and Environmental Technology, Tallinn University of Technology, Ehitajate tee 5, 19086 Tallinn, Estonia.
Polymers
|October 14, 2023
概括
在可回收的离子液体 ([mTBNH][OAC]) 中使用乙烯酸的环保纤维素化产生了具有调节性质的长链纤维素. 这些新材料显示出替代传统塑化纤维素衍生物的潜力.
科学领域:
- 绿色化学 绿色化学
- 聚合物科学 聚合物科学
- 材料科学 材料科学 材料科学
背景情况:
- 传统的纤维素化方法通常涉及强化学品,并产生大量的废物.
- 离子液体为纤维素修饰提供了一个有希望的替代介质,因为它们具有独特的溶解特性和可回收的潜力.
研究的目的:
- 合成各种长链纤维素 (酸,酸,酸,酸,酸) 以可控的取代度 (DS) 达到1.8.
- 研究使用一种新型可蒸的离子液体 ([mTBNH][OAC]) 和DMSO作为同质纤维素转化中的共同溶剂.
- 优化反应参数,分析合成的纤维素的结构,热和质性质.
主要方法:
- 在[mTBNH][OAC]离子液中用乙烯基 Ester 转化纤维素以 DMSO 作为辅溶剂.
- 反应参数的优化,包括辅溶剂含量,温度,反应时间和反应物摩尔比率.
- 使用富里埃变换红外光谱法 (FTIR),质子核磁共振 (H NMR) 和碳-13核磁共振 (C NMR) 进行了表征.
- 热和风湿学分析用于研究材料特性.
主要成果:
- 成功合成长链纤维素基与DS高达1.8.8的合成.
- 离子液体[mTBNH][OAC]显示出高的纤维素溶解性和可回收性.
- 随着反应时间,温度和乙烯基比率的增加,替代程度增加.
- FTIR和NMR证实了基链的引入,具有特定的替代顺序 (C7-O6>C7-O2>C7-O3).
- 热和学研究表明,无形阶段和融粘度增加,DS更高,这表明内部塑化.
结论:
- 开发的方法为合成可调节的长链纤维素提供了一个环保的途径.
- 合成的 Ester 具有适用于化加工的特性,并显示出替代传统塑化纤维素衍生物的潜力.
- 使用可回收的离子液体和同质的反应条件提高了纤维素修饰的可持续性.
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