Preparation And Research Of Synergistic Antibacterial And Antifouling Coatings Based On Structure Conversion

The problem of marine biofouling has always restricted people's development towards the ocean and caused huge economic losses to human beings.The hydrolyzable quaternary ammonium salt cationic bactericide has antifouling ability after hydrolysis,and has been widely used.However,after the cation is hydrolyzed,the bactericidal ability is lost and the bactericidal performance is affected.In this paper,through the structural design of high molecular polymer,the cationic polymer nanoparticles with core-shell structure with multifunctional anti-fouling mechanism were prepared.The core-shell conversion and double sterilization ability of nanoparticles were investigated,and the nanoparticles were incorporated.Antifouling coatings were prepared in polylactic acid to investigate the bactericidal and antifouling properties of the coating.First,atom transfer living radical polymerization(ATRP)is employed.Two kinds of monomers: lauryl methacrylate(LMA)and dimethylaminoethyl methacrylate(DMAEMA)were synthesized to synthesize the amphiphilic block copolymer PLMAx-b-DMAEMAy with different molecular weight distribution(x:y).A structural functional analog of the natural product capsaicin,N-(4-hydroxy-3-methoxybenzyl)acrylamide(HMBA),was synthesized.And 2-(acrylamidomethyl)-2-methoxyphenyl-2-chloroacetate(AAMPCA)was synthesized by esterification of HMBA with chloroacetylchloride,and HMBA was esterified while introducing chlorine into the HMBA.Subsequently,AAMPCA and block copolymer were added to chloroform to undergo quaternary ammonium saltation reaction,and the reaction formed a cation while the polymer self-assembled in chloroform to form a cationic block as a core,and the hydrophobic PLMA segment was a core-shell nanoparticle.A solubilization of the cation in the hydrophobic binder is achieved.The successful synthesis of various compounds was characterized by nuclear magnetic resonance spectroscopy,and the morphology and size of the nanoparticles were characterized by scanning electron microscopy.By examining the core-shell flip of nanoparticles by static water contact angle and nuclear magnetic resonance spectroscopy,we found that the nanoparticles can be flipped when the block ratio of the hydrophobic segment to the hydrophilic segment is greater than 2:1.Subsequently,the hydrolysis of the cationic structure was confirmed by ultraviolet absorption spectroscopy,and the bactericidal activity of HMBA was slowly released.The antibacterial ability of this special structure capable of slowly releasing HMBA cationic polymer is stronger than that of ordinary structure cation and HMBA by the minimum inhibitory concentration of nanoparticles.The antibacterial ability is 1+1>2.Moreover,the more the hydrophilic segment content of the cationic nanoparticles,the better the bactericidal effect.Finally,the nanoparticles are mixed into polylactic acid to form an antifouling coating and explore the ability of surface sterilization and antifouling.It was found that the ability to synergistic antifouling of various structures was achieved due to the incorporation of nanoparticles designed by a special molecular structure.The coating exhibits excellent antibacterial and antifouling properties,and exhibits an increase in the proportion of hydrophilic segments of the nanoparticles as the amount of nanoparticles mixed increases,and the sterilization and antifouling properties increase.In summary,the cationictiveness of the coating,and has a low cost and is easy to prepare,and has a good application prospect.