Doctor of Philosophy
Chemical and Biochemical Engineering
Dr Jesse Zhu
The natural world has many superhydrophobic and self-cleaning surfaces such as butterfly wings and lotus plant leaves, both well known examples of self-cleaning surfaces. Water droplets on these surfaces can pick up dirt particles and remove contamination. The significant self-cleaning ability of these surfaces has inspired many researchers to attempt to fabricate these superhydrophobic coatings, mimicking their self-cleaning properties, using different methods. Most of the superhydrophobic coatings described in current literature need to be cured in ovens and thus difficult to be applied and/or be maintained in the work place. Therefore, there is a need to develop room temperature curing superhydrophobic coatings using simple and inexpensive processes. This study demonstrates the fabrication of room temperature superhydrophobic coatings by using RTV (Room Temperature Vulcanizing) silicone rubber and fluoropolyurethane polymers. Also the effects of various parameters such as resin and solvent type, additives, coatings thickness and production methods, on the properties of superhydrophobic coatings, were evaluated. The final coatings showed contact angles higher than 145º and good UV and water durability. In addition, the superhydrophobic RTV silicone rubber coatings passed the erosion and track resistance test, a major test for high voltage insulator coatings in the industry.Conductive coatings are used in a variety of applications such as antistatic surfaces, electromagnetic interference shielding (EMI) and sensors. Despite previous research, most conductive coatings in the market that have high conductivity are made from metallic conductive fillers that are expensive and need to be compounded with polymers in high concentrations. Also, conductive mesh coatings used in the market require a complex process and should be prepared with some different processing steps. This project focuses on conductive coatings and mesh coatings that show good conductivity and have low cost. The results indicated that nano clay could improve the electrical and mechanical properties of conductive coatings. Also, conductive mesh coatings prepared by emulsion method could be a good candidate to make simple and cheap mesh coatings for electromagnetic shielding.
Seyedmehdi, Seyed Amirhossein, "Functional Coatings: Superhydrophopbic And Conductive Coatings" (2011). Electronic Thesis and Dissertation Repository. 178.