Sushanta K Mitra
Waterloo Institute for Nanotechnology, Canada
Title: Achieving dual phobic surfaces using nanostructured composite coatings
Biography
Biography: Sushanta K Mitra
Abstract
There is a significant surge in developing surfaces that can repel water and air – more particularly repelling oil in under-water systems. We have developed a composite nano-coating consisting of camphor soot particles embedded in PDMS matrix. Through proper curing process, we have demonstrated that such composite surface has self-cleaning properties with a water contact angle of 1710. It showed excellent retention of superhydrophobicity against the impact of sand particles from a height of 10–70 cm and maintained the wetting characteristics against strong acid treatment. We further performed detailed investigation of the mechanical responses of the camphor soot particle-incorporated PDMS composites by using atomic force microscopy (AFM). Using an AFM tip with a radius of approximately 10 nm, we have quantified different mechanical properties such as stiffness, the plastic work, and the effective adhesive work. Through these detailed characterization, we have also demonstrated the self-healing properties of the nanocomposite. Further modifications and chemical treatment of the composite coating provided excellent pathways towards under-water oleophobic characteristics. We have performed detailed wetting measurements in terms of Cassie-Baxter and Wenzel states of the under-water oil drops to demonstrate such under-liquid wettability. This low cost, environment friendly composite coating has large number of applications ranging from marine systems to anti-rust coatings.