快速地在现场量化用于离子溶剂中的纤维素旋转的现实光学演变
Jianyi Du1, Javier Páez2, Pablo Otero2
1Hatsopoulos Microfluids Laboratory, Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, United States.
Carbohydrate polymers
|September 2, 2023
概括
监测织织的结构演变是关键. 这项研究使用了一种新型的极化显微镜,在湿过程中非破坏性地测量纤维特性,将结构与机械性能联系起来.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 聚合物科学 聚合物科学
背景情况:
- 在现场监测复杂的流体结构演变对于织织等制造工艺至关重要.
- 目前用于织织的非破坏性测量技术有限,阻碍了工艺优化.
- 了解流体动力学和纤维结构之间的关系对于预测机械性质至关重要.
研究的目的:
- 开发和应用一种非破坏性的方法,用于在湿过程中实地监测纤维再生.
- 在纤维形成过程中同时测量纤维素/离子液体溶液的动力和光学特性.
- 建立结构-属性关系,以预测织品织性能.
主要方法:
- 一个定制的极化显微镜被用来同时在现场测量动力和光学特性.
- 在水性介质中从纤维素/离子液溶液中再生纤维被使用模型湿工艺研究.
- 通过特征跟踪提取了流动动力学,并分析了流动诱导的形态和双断裂反应.
- 应用了一种以物理为导向的质模型来关联动力学和结构测量.
主要成果:
- 该系统成功地捕获了不同线条件下的纤维的关键几何和结构信息 (拉动比率,停留时间).
- 流动动力学,形态和双断裂反应在湿过程中进行了定量测量.
- 通过将双折断反应与构成模型中的方向因子进行比较,确定了一个叠加的结构-光学关系.
- 结构特征与再生纤维的机械性能有很强的相关性.
结论:
- 开发的非破坏性协议可以有效地描述湿过程中纤维结构演变的特征.
- 该研究确定了工艺中的结构动力学和最终纤维机械性能之间的联系.
- 这种方法可以预测线性能,并优化再生纤维的制造工艺.
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