# What is the structural component of disjoining pressure?

• Yinxiao Li
In summary, disjoining pressure is a thermodynamic concept that refers to the force that separates thin films of liquid or gas from a solid surface. It can be measured using techniques like surface force apparatus and atomic force microscopy. The structural component of disjoining pressure takes into account the physical properties and molecular structure of the liquid or gas. Temperature affects disjoining pressure by altering molecular interactions and surface tension. Disjoining pressure has practical applications in materials science, surface chemistry, and colloid science, particularly in processes like coating, adhesion, and lubrication. Understanding disjoining pressure can aid in improving and designing these processes.

#### Yinxiao Li

It is widely believed that there are three components of disjoining pressure: the dispersion component (Van der Waals), the electrostatic component and the structural component. For the first two, there are some accepted formulations for calculation. However, I cannot find any equations for the structural components. Is there any papers that give an explicit equation?
Thanks!

Structural effects on physical properties aren't regular enough to be summed up in any sort of cookbook equation, sorry. If you read carefully, you'll find the other two components have a "molecular area" approximation built into them.

## 1. What is disjoining pressure?

Disjoining pressure is a thermodynamic concept that refers to the force that causes thin films or layers of liquid or gas to separate from a solid surface.

## 2. How is disjoining pressure measured?

Disjoining pressure can be measured using various techniques, such as surface force apparatus, atomic force microscopy, and optical interferometry.

## 3. What is the structural component of disjoining pressure?

The structural component of disjoining pressure refers to the contribution of the physical properties and molecular structure of the liquid or gas molecules to the overall disjoining pressure.

## 4. How does temperature affect disjoining pressure?

Temperature has a significant impact on disjoining pressure, as it can alter the molecular interactions and surface tension of the liquid or gas, thereby changing the magnitude of the disjoining pressure.

## 5. What are the practical applications of disjoining pressure?

Disjoining pressure has various applications in fields such as materials science, surface chemistry, and colloid science. It plays a crucial role in processes such as coating, adhesion, and lubrication, and understanding disjoining pressure can help in designing and improving these processes.