Surface Characteristics of a Self-Polymerized Dopamine Coating Deposited on Hydrophobic Polymer Films

Abstract

This study aims to explore the fundamental surface characteristics of polydopamine (pDA)-coated hydrophobic polymer films. A poly(vinylidene fluoride) (PVDF) film was surface modified by dip coating in an aqueous solution of dopamine on the basis of its self-polymerization and strong adhesion feature. The self-polymerization and deposition rates of dopamine on film surfaces increased with increasing temperature as evaluated by both spectroscopic ellipsometry and scanning electronic microscopy (SEM). Changes in the surface morphologies of pDA-coated films as well as the size and shape of pDA particles in the solution were also investigated by SEM, atomic force microscopy (AFM), and transmission electron microscopy (TEM). The surface roughness and surface free energy of pDA-modified films were mainly affected by the reaction temperature and showed only a slight dependence on the reaction time and concentration of the dopamine solution. Additionally, three other typical hydrophobic polymer films of polytetrafluoroethylene (PTFE), poly(ethylene terephthalate) (PET), and polyimide (PI) were also modified by the same procedure. The lyophilicity (liquid affinity) and surface free energy of these polymer films were enhanced significantly after being coated with pDA, as were those of PVDF films. It is indicated that the deposition behavior of pDA is not strongly dependent on the nature of the substrates. This information provides us with not only a better understanding of biologically inspired surface chemistry for pDA coatings but also effective strategies for exploiting the properties of dopamine to create novel functional polymer materials.

Electrodeposition of Adherent Polypyrrole Film on Titanium Surface with Enhanced Anti-corrosion Performance

“…2c, we can see that after PDA modification, lots of isolated islands were formed and the polishing scratch of Ti surface was coated by uniform thin film. It was consistent with the PDA layer formation process reported by Jiang et al [10], nanoaggregates of PDA and uniform PDA film were formed in the suspension and substrate simultaneously, and the particle of PDA will deposit onto substrate after a period of time. Fig.…”

Simple Coatings to Render Polystyrene Protein Resistant

“…The interactions between dopamine and polystyrene are believed to occur due to a combination of π-π overlap between the aromatic rings of polystyrene and the catechol rings, and the cation-π interactions between the protonated amine group of dopamine and the π-face of the styrene rings. These bonding theories imply that the DOPA and polystyrene aromatic rings align parallel to each other [43][44][45][46][47]. As there is debate about how exactly the polymer is formed and adheres to surfaces and secondary coatings [48], we tested if Pluronic F127 could in fact bind to such a polydopamine coating and create a protein rejecting interface.…”

Synthesis of Core-Shell MgO Alloy Nanoparticles for Steelmaking

“…There are numerous and varied methods for modification, including Langmuir-Blodgett deposition, monolayer self-assembly and layer-by-layer self-assembly. This can be chosen according to optimal compatibility with the specific material requirements [3][4][5][6]. However, these methods lack efficacy on a broad range of material surfaces.…”