Polydopamine Assisted Co-assembly for Fabrication of Zwitterionic Polymer Nanocoating with Efficient Aqueous Lubrication

Surface-immobilized biological macromolecules such as hyaluronic acid, mucin, etc. and surface grafted hydrophilic polymer brushes can reduce the friction of the surface of the material.Poly (2-methacryloyloxyethyl phosphorylcholine) zwitterionic polymer brush (PMPC) has excellent biocompatible super hydrophilic properties, and is considered to be the most potential bio-lubricating material.

The biomimetic polydopamine (PDA) coating materials is easy fabricated, strong adhesion capabilities with a wide range of substrates, so it has been widely used for surface modification. PDA can react with amino- or mercapto-terminated polymers to prepare various multifunctional surface coatings. Recently, PDAs was also formed co-deposited coatings with non-ionic water-soluble polymers (polyvinyl alcohol, polyvinyl pyrrolidone, polyethylene glycol, etc.) through non-covalent bond interactions. This assisted co-deposition strategy provides opportunity for the one step preparation of functional coatings on the surface of polydopamine-based materials, and can be widely used in filed of anti-pollution, antibacterial and oil-water separation etc.

Chitosan grafted zwitterionic copolymer (chitosan-g-PMPC) was prepared by grafting zwitterionic polymer (PMPC) into chitosan, and then assembled to the surface of the material substrate using polydopamine assisted co-deposition technology (Fig. 1). The results showed that, the codeposited coating shows superior lubrication performance(the friction coefficient is 0.015). the versatility of this strategy allows fabrication of lubricious polymer coatings on diverse materials surfances.

Fig. 1 Schematic illustration of fabrication of PDA/chitosan-g-PMPC codeposited coating on substrate. Coped from Ref. 1.

Reference

1. Q. Wei, F. Zhou, Q. Yue. Polydopamine assisted co-assembly for fabrication of zwitterionic polymer nanocoating with efficient aqueous lubrication. Tribology, 2019,39: