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Updated: Sep 18, 2025

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聚合物化的粘度使用基于振动模式的非亲缘理论

Ankit Singh1, Vinay Vaibhav1, Timothy W Sirk2

  • 1Department of Physics "A. Pontremoli," University of Milan, via Celoria 16, 20133 Milan, Italy.

The Journal of chemical physics
|June 23, 2025
PubMed
概括

使用非亲缘格子动力学 (NALD) 的新方法有效计算液体粘度,即使在玻璃过渡附近. 这种方法揭示了所有振动模式都有助于粘度,帮助材料设计.

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When Infrared (IR) radiation passes through a covalently bonded molecule, the bonds transition from lower to higher vibrational levels. The fundamental vibrational motions that result in infrared absorption can be classified as stretching or bending vibrations.
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Viscosity

When water is poured into a glass, it falls freely and quickly, whereas if honey or maple syrup is poured over a pancake, it flows slowly and sticks to the surface of the container. This difference in the flow of different kinds of liquids arises due to the fluid friction between the liquid layers and the liquid and the surrounding material. This property of fluids is called fluid viscosity. In this example, water has a lower viscosity than honey and maple syrup.
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Viscosity measures the resistance a fluid offers to flow and deformation. It results from internal friction between layers of fluid moving relative to one another. Dynamic viscosity, denoted by the Greek letter mu (μ), quantifies the force needed to move one fluid layer over another. For Newtonian fluids like water and air, the relationship between the shearing stress and the rate of shearing strain is linear, meaning their viscosity remains constant regardless of the applied stress.
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