Preparation And Preperties Of Capsaicin-modified Fluorosilicone Resin And Organosilicon Hybrid Hard Marine Antifouling Materials

Biofouling is a very serious problem faced by the surface of marine facilities and equipment.The adhesion of fouling organisms on the surface of underwater equipment and gear not only increases the fuel consumption of ships,but also poses hazards to engineering structures,such as accelerating biological corrosion and causing clogging of seawater intake and drainage pipes in nuclear power plants.The self-polishing antifouling coating made of acrylic resin is the mainstream in the market at present.The acrylic resin coating needs to add various metal ions as antifouling agent to prevent the occurrence of marine biological fouling,but the release of metal ions will cause pollution to the marine environment.Performance,smooth surface and low surface energy are widely used for fouling release coating,but nowadays silicone based antifouling coating has the main drawbacks of poor static antifouling effect,low adhesion to substrate and poor mechanical properties.In this paper,two new antifouling coatings were developed to address the problems of self-polishing acrylic resin coatings that are not environmentally friendly and silicone coatings with poor antibacterial properties,adhesion to substrates and mechanical properties.(1)Capsaicin-modified monomer HMBA was synthesized and copolymerized with silicon-modified acrylate and organofluorine-modified acrylate,and finally the polyacrylic acid hydrophobic coating was made by using triphenyl triisocyanate as the curing agent.The successful synthesis of the target product was demonstrated by structural characterization of the polymer using Fourier transform infrared spectroscopy and nuclear magnetic resonance hydrogen spectroscopy.Good mechanical properties of the coating were demonstrated by pencil hardness and adhesion tests.The smooth surface of HMBA was demonstrated by SEM images,EDS analysis,and contact angle measurements,and the coating has a low surface energy to resist the adhesion of fouling organisms.Biological tests on two typical marine bacteria,Hiva and Pseudomonas(97% and 98% reduction in adhesion to glass)and the diatom N.incerta(99% reduction in adhesion to glass),demonstrated that the polyacrylate coating prepared from acrylate exhibited good antibacterial and anti-algal activity.In a real sea hanging test at Qingdao port(24°33′N,118°09′E),the panels were immersed in 1 m deep seawater for 5 months,and the blank control was already full of fouling organisms,but the polyacrylate resin with HMBA still had no fouling organisms attached to it,proving its good anti-fouling effect in real sea.(2)The "antibacterial" unit acrylamide-benzothiazole was prepared by using2-aminobenzothiazole and acryloyl chloride,and then acrylamide-benzothiazole,N-vinylpyrrolidone,trifluoroethyl methacrylate,(3-mercaptopropyl)triethoxysilane(KH580),and poly(ethylene glycol)methyl ether methacrylate were used for the preparation of the "antibacterial" unit.Then zirconium sols were prepared by the hydrolysis reaction of n-propanol zirconium,and finally the "functionalized" silane capped polymers and zirconium dioxide zirconium sols were prepared by the sol-gel reaction to produce transparent hybrid coating.Structural characterization of the polymers using Fourier transform infrared spectroscopy and nuclear magnetic resonance hydrogen spectroscopy demonstrated the successful synthesis of the target products.The long-chain "functionalized" silane-capped polymeric fraction was able to give good flexibility to the coating,and the coating did not crack after several bending cycles.The addition of zirconium dioxide sols increased the pencil hardness of the coating from 2H to 6H and the adhesion force from 1.5 to 2.8 Mpa.The surface roughness of the coating was measured at the nanometer level according to AFM and the contact angle measurements demonstrated that the coating had a lower surface energy to better resist the adhesion of fouling organisms.Biological tests on two typical marine bacteria,Schifferella and Pseudomonas(99% and 99% reduction in adhesion to comparative glass)and diatom N.incerta(99% reduction in adhesion to comparative glass),demonstrated that the presence of benzothiazole moieties gave the coating good anti-fouling properties.