Synergies in lubrication

• Published in: Physical chemistry chemical physics : PCCP 2017, Vol.19 (35), p.23677-23689
• Main Authors: D dinait, Andra, Claesson, Per M
• Format: Article
• Language: English
• Subjects: Articular-Cartilage Surfaces; Atomic-Force Microscopy; Boundary Lubrication; Cationic Polyelectrolyte; Diblock Copolymer; Enhanced Wear Protection; Hyaluronic-Acid; Hydration Lubrication; Polymer-Bearing Surfaces; Shear Forces
• ISSN: 1463-9076; 1463-9084; 1463-9084
• DOI: 10.1039/c7cp03517a

To slide surfaces against each other with application of a minimum force and minimum wear has been important since ancient times, and it remains equally important today. The use of oil-soluble lubricants is widely spread in technology, whereas living organisms have developed water-soluble lubricants to facilitate sliding motions. In this perspective article we focus on water-based lubrication in the boundary lubrication regime, and particularly lubrication synergies. This focus has, of course, found inspiration from the outstanding lubrication properties of synovial joints. It has ignited significant amount of research, mostly aimed at answering the question: Which molecule is the magic biolubricant? Different research groups have advocated different answers, and the debate has been intensive. In this article we argue that the question in itself is inappropriate. The relevant question is rather the following: How do molecules work in synergy to provide superior lubrication? In living organisms the aqueous medium is used for providing low friction forces. This is achieved by synergistic actions of different biomolecules that together accomplish a high load bearing capacity and sustain an easily sheared water layer.