Marine biofouling inhibition by polyurethane conductive coatings used for fishing net

摘要

The purpose of the present study is to develop a new conductive coating for application on fishing nets that can be used as an anode, while submersed in the sea, to generate free chlorine which will in turn inhibit marine biofouling. To confirm the durability and viability of this coating, long-term field tests were carried out in the Nanao harbor in Taiwan. Electrical resistivity tests showed that polyurethane resin with carbon black and graphite can demonstrate the lowest resistivity: 0.06 Ωm. This sample also generated optimal quantities of free chlorine, which performs excellent antifouling properties. The use of carbon black in conjunction with graphite did prove to yield greater benefits. A 500-day field test showed that the PU-CG conductive coatings reduced the quantity of marine biofouling attached to the cage by approximately 79%. Furthermore, the chlorine produced was within safe levels, and judged not to pollute the sea. However, this antifouling system still shows durable problems which remain to be considered.