Adhesion Properties of Self-Polymerized Dopamine Thin Film

摘要

We report an experimental study of the adhesion properties of polydopamine thin films and their bondingbehavior on polymer, glass and metal surfaces. Dopamine is able to adsorb onto all surfaces and self-polymerize into athin hydrophilic film. Dynamic contact angle measurements revealed a large contact angle hysteresis between advancingand receding angles and a possible hydration layer when exposed to water. Polydopamine-coated surfaces in air arerelatively inert having a low self-adhesion compared with polydimethylsiloxane elastomer surfaces, reflecting the nonconformal,glassy nature of polydopamine thin films. The dopamine aqueous solution was found able to bond two rigidsurfaces (e.g. aluminum and glass) but it might not be suitable for joining soft or flexible polymer surfaces aspolydopamine films are glassy and subject to internal cracks induced by the mismatch of elastic modulus. The researchfindings provide insights into the potential application of dopamine self-polymerization for adhesive bonding or joining ofdissimilar materials.