Research Of Silicone Modified Polyurethane Marine Antifouling Coatings

Marine antifouling coating is an important protective material for Marine engineering and equipment,which plays a very important role in the development and utilization of Marine resources.Among the currently Marine antifouling coatings,low surface energy antifouling coatings will not damage the Marine environment and will be the main development direction in the future.As countries around the world continue to attach importance to marine environmental protection,environmentally friendly low surface energy antifouling coatings have become the focus of research.Among them,Organic silicon low surface energy type marine antifouling paint has been developed rapidly and widely used,but it gradually exposes the shortcomings of poor comprehensive mechanical properties of paint films,and needs to be further improved.Aiming at the technical requirements for improving the performance of silicone marine antifouling coatings,using three different hydrophilic segments,three different modified random copolymers were synthesized,and the influence of hydrophilic materials on the performance of silicone substrates was compared and analyzed.The specific research content and research results are as follows:1)Using isophorone diisocyanate(IPDI),polyethylene glycol(PEG),hydroxypropyl silicone oil(DY)as raw materials to prepare PEG-DY random copolymer.The infrared spectroscopy,DSC and other test methods confirmed that the modified resin was a random copolymer of PEG-DY.Through a comprehensive test of the modified resin surface performance,acid and alkali resistance,water resistance and algae suppression And research,the results show that the acid and alkali resistance of the modified resin have been improved.When the molecular weight of DY increases,the contact angle increases significantly,but the increase in the molecular weight of PEG will cause the contact angle to decrease.When modified resin is PEG400-DY3000,the maximum contact angle can reach 107.68°,the water absorption rate is 6.74%,the elongation at break is 20.47%,and the elastic modulus is 27.59MPa.2)PCL-DY resin was prepared by polymerizing polycaprolactone(PCL)with different relative molecular weights and hydroxypropyl silicone oil resin(DY)with different molecular weight and hexamethylene diisocyanate(HDI).The random copolymer structure of PCL-DY was confirmed by Fourier infrared and XRD.The surface performance,acid and alkali salt resistance,water resistance,degradation performance,and algae suppression performance of the modified resin were tested and studied in detail.The results show that the introduction of weak hydrophilic segment PCL with high hydrophobic segment can significantly improve the contact angle of the paint film.The surface energy of the film decreases,and the elongation at break also increases significantly.Finally,the modified resin is PCL2500-DY3000,the contact angle was 110.05°,the water absorption rate was 1.09%,the elongation at break was 182.47%.The adhesion experiment of diatom shows that the synthesized PCL-DY resin has little adhesion and has an excellent antifouling ability.3)Polyurethane modified organosilicon low surface energy antifouling coatings were prepared by using Polymerize polyester polyols(PCLx/PLAy)with different molar ratios,hydroxypropyl silicone oil resins(DY)with different molecular weights and hexamethylene diisocyanate(HDI).The structure of PCLA-DY random copolymer was characterized and confirmed by Fourier infrared.Through detailed tests on the surface performance,acid and alkali resistance,water resistance,degradation performance and algae suppression performance of the modified resin,the influence of hydrophilic and degradable PLA content of the degradable component in the PCLA ratio on the performance of the paint film was mainly investigated.The experimental results show that the introduction of PLA can greatly increase the contact angle of the paint film,Finally,the resin is PCLA6:4-DY3000,the contact angle is 116.39 °,The water absorption rate is 2.63%,the elongation at break is 36.29%.4)The synthetic resin was prepared into a low surface energy antifouling coating.The effect of three different hydrophilic segments on anti-fouling performance was studied through the real sea hanging board.The results show that the larger the molecular weight of PEG(or the greater the molecular weight of DY),the better the antifouling performance in PEG-DY antifouling coatings;The larger the molecular weight of PCL(or the greater the molecular weight of DY),the better the antifouling performance in PCL-DY antifouling coatings;In PCLA-DY antifouling coatings,the lower the content of PLA in PCLA(or the greater the molecular weight of DY),the better the antifouling performance.Through the contact Angle measurement,mechanical properties,surface morphology,antifouling effect and other comprehensive comparisons of the three different hydrophilic segment modified antifouling coatings found that PEG-DY antifouling coatings have better comprehensive performance,and the real seaboard has the best antifouling effect and the best antifouling ability.