Dynamics of drop absorption by a swelling fiber
Pierre Van de Velde1, Suzie Protière2, Camille Duprat1
1LadHyX, CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, UMR 7646, 91128 Palaiseau, France. camille.duprat@ladhyx.polytechnique.fr.
Soft Matter
|June 7, 2021
Summary
Fiber geometry and drop volume significantly impact solvent absorption time. Larger drops can saturate the fiber, drastically increasing absorption duration, as explained by a new model.
Area of Science:
- Materials Science
- Fluid Dynamics
- Polymer Science
Background:
- Solvent absorption by fibrous materials can alter their mechanical properties and shape.
- Understanding the dynamics of liquid-solid interactions on fibers is crucial for material design.
Purpose of the Study:
- To experimentally investigate the absorption dynamics of a single drop on a swellable fiber.
- To analyze the influence of fiber geometry and drop volume on absorption time.
- To develop a model for predicting fiber swelling and drop absorption.
Main Methods:
- Experimental observation of single drop absorption on a swellable fiber.
- Systematic variation of fiber geometry and drop volume.
- Development and application of a pseudo-diffusive model.
Main Results:
- Total absorption time is highly dependent on fiber geometry and drop volume.
- Fiber curvature limits drop spreading, even for fully wetting fluids.
- Drops exceeding a critical volume cause local fiber saturation, significantly increasing absorption time.
Conclusions:
- A simple pseudo-diffusive model effectively explains drop absorption and fiber swelling dynamics.
- The model provides quantitative predictions for total absorption time.
- Fiber geometry and drop volume are critical parameters in solvent-fiber interactions.
Related Concept Videos
01:14Adhesion
42.4K
Adhesion occurs when one type of molecule is attracted to a different molecule. Water exhibits adhesive properties in the presence of polar surfaces, such as glass or cellulose in plants. For instance, when water is poured into a glass, the positively charged hydrogen molecules of water are more attracted to the negatively charged oxygen molecules in the silica than to the oxygen in neighboring water molecules.
Capillary action is a result of water’s adhesive tendencies. When a narrow...
Capillary action is a result of water’s adhesive tendencies. When a narrow...
42.4K
01:09Theories of Dissolution: The Danckwerts' Model and Interfacial Barrier Model
545
Various dissolution theories provide insight into the factors that influence the dissolution rate. Danckwerts' Model suggests that turbulence, rather than a stagnant layer, characterizes the dissolution medium at the solid-liquid interface. In this model, the agitated solvent contains macroscopic packets that move to the interface via eddy currents, facilitating the absorption and delivery of the drug to the bulk solution. The regular replenishment of solvent packets maintains the...
545
01:20Types of Damping
7.1K
If the amount of damping in a system is gradually increased, the period and frequency start to become affected because damping opposes, and hence slows, the back and forth motion (the net force is smaller in both directions). If there is a very large amount of damping, the system does not even oscillate; instead, it slowly moves toward equilibrium. In brief, an overdamped system moves slowly towards equilibrium, whereas an underdamped system moves quickly to equilibrium but will oscillate about...
7.1K
01:07Damped Oscillations
6.4K
In the real world, oscillations seldom follow true simple harmonic motion. A system that continues its motion indefinitely without losing its amplitude is termed undamped. However, friction of some sort usually dampens the motion, so it fades away or needs more force to continue. For example, a guitar string stops oscillating a few seconds after being plucked. Similarly, one must continually push a swing to keep a child swinging on a playground.
Although friction and other non-conservative...
Although friction and other non-conservative...
6.4K
01:18Rise of Liquid in a Capillary Tube
2.6K
When very thin cylindrical tubes, called capillaries, are dipped in a liquid, the liquid rises or falls in the tube compared to the surrounding liquid. This phenomenon is called capillary action. Capillary action occurs due to the combination of two opposing forces: the cohesive forces of the liquid, which cause it to stick to itself and form a rounded shape, and the adhesive forces between the liquid and the walls of the container, which cause the liquid to be attracted to the container walls.
2.6K
01:15Theories of Dissolution: Diffusion Layer Model
1.2K
Dissolution, the process by which drug particles dissolve in a solvent, is explained by the diffusion layer model, a theoretical framework that simulates the absorption of oral drugs and allows us to analyze experimental data.
This process starts with a thin layer, saturated with the drug, forming at the interface between the solid and liquid. The solute then diffuses from this layer into the main solution. The Noyes-Whitney equation suggests that the rate of dissolution relies on the diffusion...
This process starts with a thin layer, saturated with the drug, forming at the interface between the solid and liquid. The solute then diffuses from this layer into the main solution. The Noyes-Whitney equation suggests that the rate of dissolution relies on the diffusion...
1.2K