通过高温预冷提高再生纤维素的机械性能
Yuxiu Yu1,2, Weiku Wang1,3, Yaodong Liu1,2
1CAS Key Laboratory of Carbon Materials, Institute of Coal Chemistry, Chinese Academy of Sciences, 27 Taoyuan South Road, Taiyuan 030001, China.
Materials (Basel, Switzerland)
|October 16, 2024
概括
在LiCl/DMAc溶液中对纤维素进行化前处理,可显著增强再生纤维素材料. 这一过程改善了结晶性,分子方向和机械性能,如抗拉强度和压缩模量.
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
- 生物材料工程 生物材料工程
背景情况:
- 纤维素是一种多功能生物聚合物,在织品,包装和生物材料中具有应用.
- 再生纤维素材料通常在机械性能和结构完整性方面面临限制.
- 优化纤维素加工对于释放其全部潜力至关重要.
研究的目的:
- 为了研究预凝对溶于LiCl/DMAc溶液中的纤维素的影响.
- 描述预凝对再生纤维素结晶性,分子定向和机械性能的影响.
- 评估预凝对增强纤维素基材料的潜力.
主要方法:
- 纤维素被溶解在LiCl/DMAc溶剂中.
- 对纤维素溶液进行了预凝处理,持续时间各不相同 (3天和7天).
- 准备了再生纤维素纤维和水凝.
- 使用X射线衍射 (XRD) 分析晶度和分子方向.
- 进行了机械测试 (拉力强度,压缩模量).
主要成果:
- 化前的过程使纤维素结晶度从55%增加到59%.
- 在XRD分析中,预先凝的样本显示了纤维素链对齐的改善.
- 预凝纤维的拉伸强度增加了30%.
- 与未经处理的纤维相比,预凝纤维的压缩模量翻了一番.
结论:
- 预凝是一种有效的方法,可以提高再生纤维素的结构秩序和机械性能.
- 优化的纤维素材料在先进的应用中表现出更好的性能.
- 对化前效益的进一步研究可以推动基于纤维素的材料的创新.
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