Surface physical structure and durability of superhydrophobic wood surface with epoxy resin

Abstract

In this study, a superhydrophobic wood surface was prepared with amino-functionalized nano-silica (SiO2) particles, epoxy resin (EP) of different curing times, and octadecyltrichlorosilane (OTS). The micro-nano structures of the wood samples were represented by scanning electron microscopy (SEM), while the hydrophobicity and durability of the hydrophobic effect was shown by the contact angle (CA) tests. The results indicated that the optimal curing time of EP was 4 h, such that the wood surface exhibited promising superhydrophobicity with a static CA of 155.4° and a sliding angle (SA) of 3.9°. The different curing time of EP had a remarkable influence on the roughness and the pore structure type of superhydrophobic wood surface. In terms of the Cassie-Baxter theory, the increase of CA on the wood surface was ascribed to the presence of secondary air pores and rough structure in the solid-liquid interface. The obtained wood surface not only possessed excellent adhesion stability and anti-aging properties, but also a resistance to acidic solutions, organic solvents, and mechanical abrasion.