Synthesis of hydrophilic epoxy resin/epoxidized tannic acid interpenetrating network resin and evaluation of its anti-moss coating properties

The resins with anti-moss properties play an important role in the performance of the final coatings. With the increasing demand for anti-fouling coatings, it is necessary to provide resins that contain hydrophilic chain segments to increase the efficiency and erosion of the final coating. In this article, epoxidized tannic acid resin (ETAR), which has hydrophilic chain segments, is prepared and epoxy resin (EP) forms ETAR/EP interpenetrating polymer network under the simultaneous curing process. The successful preparation of ETAR/EP was confirmed through infrared spectrum analysis (FTIR). The produced IPN was also subjected to hydrophilic and mechanical tests. The results show that tannic acid can effectively improve the hydrophilicity of the film-forming resin and at the same time maintain its mechanical properties. From the hydrophilic and mechanical properties of this coating, it can be concluded that the general properties of ETAR/EP are optimal when the amount of ETAR in the resin composition is 45%. The test of the painted panel immersed in the real environment showed that, under experimental conditions, the anti-moss effect of the coating prepared by the hydrophilic ETAR/EP resin was better than that of the conventional epoxy anti-moss coating. The ETAR/EP resin-based coating showed better anti-moss effect than commonly used epoxy coating in immersion test. Adding ETAR to EP significantly decreased the contact angle, from approximately 90 degrees to 60 degrees. This decrease indicates an increase in the hydrophilicity of the coating surface.