Probing the Interaction Forces of Phenol/Amine Deposition in Wet Adhesion: Impact of Phenol/Amine Mass Ratio and Surface Properties

Mussel-inspired phenol/amine deposition in wet adhesion provides a cost-effective strategy to readily fabricate functional coatings for a wide range of applications. The adhesion of phenol/amine to different substrates and the cohesion between phenol/amine are believed to play critical roles during the deposition process. However, the understanding on the correlation between the deposition capability and interaction behavior involved in the coating formation still remains incomplete, which limits further developing phenol/amine-based functional materials and coatings. In this work, we correlated the interaction forces between two phenol/amine coatings and between phenol/amine coating and different substrate surfaces with the deposition capability of phenol/amine using surface forces apparatus and atomic force microscopy. The mass ratio of phenol and amine was found to significantly influence the deposition behavior through regulating the surface properties of phenol/amine aggregates' cohesion strength between phenol/amine coatings. Furthermore, the strong adhesion measured between phenol/amine coating and substrates with varying surface chemistry was demonstrated to be able to effectively initiate the surface-independent phenol/amine deposition as well as the continuous growth of phenol/amine coatings. This work provides useful insights into the fundamental understanding of the interactions and deposition mechanism during phenol/amine deposition process, with implications for developing advanced phenol/amine-based coating materials for a wider range of applications.