在增强纤维素薄膜中通过单轴拉伸来构造受限无形分子链
Jing Wang1, Shi-Peng Chen1, De-Long Li1
1College of Polymer Science and Engineering and State Key Laboratory of Polymer Materials Engineering, Sichuan University, Chengdu 610065, China.
Carbohydrate polymers
|May 6, 2024
概括
拉伸纤维素水凝可以产生高性能再生纤维素薄膜 (RCF). 增强的机械性能主要是由于无形分子链的限制放松,而不仅仅是晶体结构.
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
- 纳米技术纳米技术
背景情况:
- 通过拉伸制造高性能纤维素薄膜是有效的.
- 晶体结构与无形分子链在机械增强中的作用仍然不清楚.
研究的目的:
- 调查决定纤维素薄膜增强机械性能的关键因素.
- 了解无形分子链对机械性质的贡献.
主要方法:
- 单轴拉伸的纤维素水凝与双重交联网络.
- 在拉伸状态下干燥,形成再生纤维素薄膜 (RCF).
- 层次结构的表征 (微观形态,晶体结构,分子放松).
- 分析使用动态机械分析的二维相关谱和哈夫里利亚克-内加米拟合.
主要成果:
- 实现了高性能RCF,其拉伸强度为154.5MPa,弹性模量为5.4GPa.
- 证明增强的机械性能主要归因于拉伸诱导的紧密包装和无形分子链的限制放松.
- 系统地描述了从微小到纳米尺度的层次结构.
结论:
- 无形分子链的限制放松是RCF增强机械性能的关键因素.
- 这一发现为设计高性能,环保的纤维素薄膜提供了宝贵的指导.
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