Theory of a Possible Mechanism for Lubrication and Surface Protection by an Electrically Neutral Hydrogels

TL;DR

This paper proposes a theoretical mechanism by which neutral hydrogels can prevent adhesion and provide lubrication when in contact with surfaces, especially when immersed in fluid, with potential applications like contact lens protection.

Contribution

It introduces a novel theoretical model explaining how surface-anchored polymers in neutral hydrogels can prevent adhesion and enable lubrication in fluid environments.

Findings

Polymers protruding from hydrogels can prevent adhesion.

The mechanism is effective only when the gel and surface are immersed in fluid.

Optical properties of gel-surface interfaces are discussed for experimental study.

Abstract

It is demonstrated that polymers sticking out of the surface of a neutral hydrogel are capable of preventing adhesive forces from pulling a hydrogel into close contact with a surface against which it is pressed. The proposed mechanism for lubrication or surface protection suggests a possible mechanism for protecting the cornea from a contact lens, which is held against the eye by Laplace pressure. This mechanism, however, is only able to keep a gel coated surface from sticking to a surface against which it is pressed, if the gel and surface are bathed in fluid. Expected optical properties of the gel-surface interface are discussed, in order to suggest possible ways to study the gel-solid interface experimentally.