Silicone/Ag@SiO2 core–shell nanocomposite as a self-cleaning antifouling coating material

摘要

The effects of Ag@SiO _(2) core–shell nanofiller dispersion and micro-nano binary structure on the self-cleaning and fouling release (FR) in the modelled silicone nano-paints were studied. An ultrahydrophobic polydimethylsiloxane/Ag@SiO _(2) core–shell nanocomposite was prepared as an antifouling coating material. Ag@SiO _(2) core–shell nanospheres with 60 nm average size and a preferential {111} growth direction were prepared via a facile solvothermal and a modified St?ber methods with a controlled shell thickness. Ag@SiO _(2) core–shell nanofillers were inserted in the silicone composite surface via solution casting technique. A simple hydrosilation curing mechanism was used to cure the surface coating. Different concentrations of nanofillers were incorporated in the PDMS matrix for studying the structure–property relationship. Water contact angle (WCA) and surface free energy determinations as well as atomic force microscopy and scanning electron microscope were used to investigate the surface self-cleaning properties of the nanocomposites. Mechanical and physical properties were assessed as durability parameters. A comparable study was carried out between silicone/spherical Ag@SiO _(2) core–shell nanocomposites and other commercial FR coatings. Selected micro-foulants were used for biological and antifouling assessments up to 28 days. Well-distributed Ag@SiO _(2) core–shell (0.5 wt%) exhibited the preferable self-cleaning with WCA of 156° and surface free energy of 11.15 mN m ~(?1) .