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塑形悬浮液:在粘弹性介质中使用振荡来稳定异构性
Sebastian Gassenmeier1, Christophe De Graaf2, Anja Vananroye1
1Department of Chemical Engineering, KU Leuven, Celestijnenlaan 200J, Leuven, 3001, Vlaams-Brabant, Belgium.
Journal of colloid and interface science
|May 21, 2025
概括
振荡流使粒子在低切割速率下轻松地排列成长串,克服了对异性质材料组装稳定切割的局限性. 这种累积对齐过程适用于各种应用,包括肉类类型和导电复合材料.
科学领域:
- 材料科学 材料科学 材料科学
- 类风病学 类风病学 类风病学
- 聚合物科学 聚合物科学
背景情况:
- 产生异性质结构对于诸如肉类类似物和导电复合材料等应用至关重要.
- 对于粘弹性液体中的颗粒对齐的传统方法需要高切割率或高度弹性的流体,这限制了实际实施.
- 由于处理参数约束,现有流程往往涉及繁的额外步骤.
研究的目的:
- 开发一种更简单的过程,以产生高度异性质的结构和特性.
- 研究在粘弹性液体中用于粒子对齐的振荡流的使用.
- 为了比较振荡流的有效性与传统的稳定剪切方法.
主要方法:
- 利用振荡流来诱导粘弹性液体中的粒子对齐.
- 比较调整效率和弦形成,切割速率明显低于稳定切割.
- 在振荡流中通过流量逆转来研究累积对齐.
- 使用叠加的振荡和稳定切割来演示对齐结构的挤出.
主要成果:
- 振荡流在切削速率下实现粒子对齐,比稳定切削低两倍.
- 在振荡流中的对齐是累积的,因为通过流量逆转来防止弦断裂,从而使无限的异性流组合成为可能.
- 稳定的剪切对齐是非累积的,因为韦森伯格数依赖的弦稳定性和断裂.
- 该机制适用于非理想粒子,并使挤压对齐结构成为可能.
结论:
- 振荡流是一种更有效和更容易使用的方法,用于在粘性弹性材料中创建异型结构.
- 这种技术克服了传统稳定剪切方法的局限性,提供了更广泛的应用.
- 在振荡流下对齐的累积性质允许潜在的无限异型组合,有利于先进的材料设计.
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