On the Relation between Hamaker Constant and Contact Line Friction

Area of Science:

• Surface Science
• Materials Science
• Physical Chemistry

Background:

• Optimizing fluid-substrate interactions is crucial for applications like coatings and microfluidics.
• The relationship between Hamaker constant and contact line friction is not well understood.
• Existing research often studies these parameters independently, limiting control over interfacial behavior.

Purpose of the Study:

• To investigate the correlation between the Hamaker constant and contact line friction.
• To provide deeper insights into wetting dynamics for designing advanced functional surfaces.
• To establish a fundamental understanding of the wetting framework by linking interfacial properties.

Main Methods:

• Utilized molecular dynamics (MD) simulations.
• Employed molecular kinetic theory (MKT) to analyze interfacial properties.
• Simulated a thin water film on a substrate with varied water-substrate interaction strengths, emulating good wetting conditions.

Main Results:

• The Hamaker constant remained relatively constant for a specific liquid-solid system.
• Contact line friction decreased with increasing temperature and weaker water-substrate interactions.
• A fundamental correlation was established between the Hamaker constant and MKT parameters, including contact line friction.

Conclusions:

• The study successfully established a correlation between the Hamaker constant and contact line friction.
• Findings enhance the fundamental understanding of wetting dynamics and interfacial behavior.
• Results can guide the development of efficient coatings, lubricants, and microfluidic systems.