Influence of Glycol Molecular Configuration on Friction

Abstract

Boundary or mixed friction studies on a wide range of synthetic lubricants and mineral oils demonstrated that ethylene glycol gave higher static friction and much lower kinetic friction than did other lubricants tested. To investigate this unusual properly of ethylene glycol, poly-hydroxy alcohols of various molecular configurations were evaluated. The results indicate, that kinetic friction increases and static friction decreases as either the number of atoms between primary hydroxyl groups increases or primary hydroxyl groups are replaced with secondary hydroxyl groups. Surface coatings containing oxidation products of the glycols are believed to be responsible for the observed friction characteristics.