Preparation Of Modified Cu₂O NPs And Marine Antifouling Performance

Marine fouling is a significant problem in the development of Marine resources.When sea creatures are attached to the bottom of the boat,navigation resistance increases by 80percent,and speed decreases by 15%.This brings excellent economic harm to Marine activities.In order to solve this massive problem,people have launched much antifouling technology.The Marine antifouling coating is the most economical and effective method,and the critical role in the antifouling coating is the antifouling agent.At present,Cu₂O is the mainstream antifouling agent on the market.However,in the process of use,it often needs to add more than 40%to achieve the ideal effect,making the Cu₂O effective utilization rate low,causing much waste.From the perspective of the ecological environment,a lot of use of Cu₂O as an antifouling agent is not an ideal long-term choice.In this paper,the antimicrobial and antialgal properties of modified nanometer Cu₂O were studied,and it was applied to Marine antifouling coatings.The main work contents are as follows:1.Firstly,using N,N-dimethyl-3-（trimethoxysily）-1-propylamine and halides with different carbon chain lengths as raw materials,a series of quaternary ammonium salts with different carbon chain lengths（QAS-X）,modified nano Cu₂O with different QAS-X.The structure and performance of modified nano Cu₂O were characterized by infrared spectroscopy（FT-IR）,thermogravimetry（TG）,Zeta potential,etc.The results showed that:compared with nano Cu₂O modified nano Cu₂O quaternary ammonium salt,The minimum inhibitory concentration is 0.25 mg/mL,and the highest algae inhibition rate can reach99.73%2.Secondly,prepare marine antifouling paint with quaternary ammonium salt modified nano Cu₂O as an antifouling agent and acrylic resin as substrate.The additional amount of Cu₂O in the antifouling coating is only 6%.SEM-Mapping results show that the quaternary ammonium salt modified nano Cu₂O has a good dispersion performance in the coating,and the stability in the composite coating is improved.The Cu²⁺in the coating can finally reach a stable release,which is a necessary condition for the long-term antifouling of the composite antifouling coating.In addition,the coating has an excellent inhibitory effect on Escherichia coli and Staphylococcus aureus.It has an excellent inhibitory effect on the growth of three kinds of marine algae,indicating that the antifouling coating has excellent antifouling ability.3.Finally,an antifouling agent with triple synergy（QACOS@PAL@Cu₂O）was prepared using nano-Cu₂O,quaternary ammonium salt,and chitooligosaccharides as raw materials.The structure of nano-Cu₂O modified with quaternized chitosan oligosaccharides（QACOS@PAL@Cu₂O）was characterized by infrared spectroscopy（FT-IR）,hydrogen nuclear magnetic spectroscopy（~1H-NMR）and Zeta potential.The inhibitory properties of Staphylococcus aureus and Vibrio alginolyticus and the growth inhibition of three marine algae.The results showed that the minimum inhibitory concentration（MIC）of QACOS@PAL@Cu₂O against Escherichia coli was 0.05 mg/mL,and the minimum bactericidal concentration（MBC）was 0.15 mg/mL;the minimum inhibitory concentration（MIC）for Staphylococcus aureus The minimum bactericidal concentration（MBC）is 0.15mg/mL;the minimum inhibitory concentration（MIC）for Vibrio alginolyticus is 0.0025mg/mL,and the minimum bactericidal concentration（MBC）is 0.005 mg/mL.Compared with the unmodified nano-Cu₂O,the minimum inhibitory concentration and minimum bactericidal concentration have been reduced.The inhibitory effect on algae（Nitzschia closterium f.minutissima,Phaeodactylum tricornutum,and Dicrateria zhanjiangensis）has also been improved.