Low Surface Energy Marine Antifouling Paint Modified With Nano SiO₂

In consideration of serious economic loss in shipping business caused by the halobios'sticking every year and thinking of oceanic pollution caused by oceanic antifouling paint, on 1st January 2008, the IMO forbad the use of organotin self-polishing marine antifouling paints. Recent years, there has been more and more researches and developments of marine organotin-Free antifouling paint home and abroad, as well as its application. However, the research and development of low surface energy antifouling paints has been in progress, without any practical application.This research synthetically modifies acrylic resin which is applied widely adopting organosilicon monomer with the property of low surface energy. Moreover, on the basis of pilot study in Lab, prepare marine antifouling paint by using small molecular silane modified resin as film-forming substance. By comparison of the conventional properties including adhesion, impact strength, toughness, hardness, etc. of paints prepared by different preparing processes and different spraying processes, as well as the macro-observation and the analysis of SEM micro-morphology of paint film prepared by different processes, the author finds out the best preparing process and spraying process. Though investigating the addition amount of nanometer-sized SiO2 and resin and the effect on coating property by the value of PVC, the research ascertains the CPVC value of paint. Combing with the best synthetic process of resin and coating and other factors, the author finds out the best formula to prepare paints. Use contact angle measuring instrument to measuring contact angle between paint surface and water by means of goniometry, as well as synthetically testing every conventional property of paint. The result states that when proportion of the addition amount of nanometer-sized SiO2 to pigment and filler is 40%, the proportion of resin to pigment and filler being 62.5%, the value of CPVC being 60%, the contact angle between paint surface and water reaches 150°, every conventional property parameter of paint reaches national standards. When using SEM to analyze the morphology of coating prepared by the best formula, the author finds out that nanometer-sized SiO2 and other micron-sized pigment and filler forms plenty of nanometer-sized and micron-sized mastoids and channels, as well as groove with micro rough hydrophobic structure, producing the ideal hydrophobic effect.