Related Experiment Video
Updated: May 5, 2026
13:10
Creating Adhesive and Soluble Gradients for Imaging Cell Migration with Fluorescence Microscopy
Published on: April 4, 2013
12.6K
Surface mobility gradient and emergent facilitation in glassy films.
Qiang Zhai1, Xin-Yuan Gao2, Chun-Shing Lee3
1School of Physics, MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, Xi'an, Shaanxi, 710049, China. yangsen@mail.xjtu.edu.cn.
Soft Matter
|May 17, 2024
Summary
Confining glassy polymers into thin films alters their properties. A new lattice model explains transport behavior, showing a shift from viscous flow to surface-dominated flow at lower temperatures.
Area of Science:
- Polymer physics
- Materials science
- Condensed matter physics
Background:
- Confining glassy polymers into films significantly alters their local and averaged properties.
- Understanding these modifications is crucial for designing advanced materials.
Purpose of the Study:
- To present a lattice model for glassy polymer films.
- To analyze spatially varying viscosity and transport properties.
- To explain void-mediated facilitation behaviors without elasticity.
Main Methods:
- Development of a lattice model for film geometry.
- Analysis of spatially varying viscosity.
- Simulation of transport properties in glassy films.
Main Results:
- The model successfully reproduces experimental film mobility measurements.
- A crossover from viscous flow to surface-dominated flow is observed with decreasing temperature.
- Visualization of a highly mobile front propagation induced by the free surface.
Conclusions:
- The lattice model provides a microscopic explanation for observed glassy phenomena in polymer films.
- Void-mediated facilitation and surface effects are key to understanding transport properties.
- The study offers insights into the behavior of confined glassy polymers.
Related Concept Videos
01:09Cell Migration
16.6K
Cell migration, the process by which cells move from one location to another, is essential for the proper development and viability of organisms throughout their life. When cells are not able to migrate properly to their ordained locations, various disorders may occur. For example, disruption in cell migration causes chronic inflammatory diseases such as arthritis.
16.6K
02:57Surface Tension, Capillary Action, and Viscosity
28.7K
Surface Tension
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
28.7K
01:26Membrane Fluidity
14.1K
Membrane fluidity is explained by the fluid mosaic model of the cell membrane, which describes the plasma membrane structure as a mosaic of components—including phospholipids, cholesterol, proteins, and carbohydrates—that gives the membrane a fluid character.
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is...
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is...
14.1K
01:28Types of Membrane Protrusions
3.0K
The protrusion of the cell surface is an initial step for several cellular processes, including cell migration, phagocytosis, and neurite outgrowth. These membrane protrusions are a result of cytoskeletal rearrangement. The most widely observed cell protrusions include lamellipodia, pseudopodia, filopodia, microvilli, invadopodia, and podosomes. These protrusions can be of two types — static or dynamic.
The microvilli, an example of stable protrusions, are finger-like projections...
The microvilli, an example of stable protrusions, are finger-like projections...
3.0K
01:16Surface Tension and Surface Energy
3.2K
When a paint brush is immersed in water, the bristles wave freely inside the water. When it is taken out, the bristles stick together. The reason behind this effect is surface tension.
Consider a beaker filled with liquid. The bulk molecules in the liquid experience equal attractive forces on all sides with the surrounding molecules. However, the surface molecules experience a net attractive force downward due to the bulk molecules. The surface of the liquid behaves like a stretched membrane,...
Consider a beaker filled with liquid. The bulk molecules in the liquid experience equal attractive forces on all sides with the surrounding molecules. However, the surface molecules experience a net attractive force downward due to the bulk molecules. The surface of the liquid behaves like a stretched membrane,...
3.2K
01:13Contact Angle
27.7K
When a solid is dipped inside a liquid, the liquid surface becomes curved near the contact. For some solid–liquid interfaces, the liquid is pulled up along the solid, while for others, the liquid surface is convex or depressed near the solid surface. This phenomenon can be explained using the concept of cohesive and adhesive forces.
The adhesive force is the molecular force between molecules of different materials, that is, between the molecules of the solid and the liquid. The cohesive...
The adhesive force is the molecular force between molecules of different materials, that is, between the molecules of the solid and the liquid. The cohesive...
27.7K