Preparation Of Polyurushiol-loaded Silver Nanoparticles By One-step Method And Its Antifouling Properties

Marine biofouling has been a global problem for the exploration and development of the marine resources.Many technologies have been developed to alleviate this problem.Among them,the application of marine antifouling coating is the most effective method.Cu₂O is currently the mainstream antifouling agent on urban surfaces,but from the perspective of ecological environment,Cu₂O is not a long-term ideal choice.Silver nanoparticles(AgNPs)are considered a promising antifouling agent due to their long-term antibacterial activity and relatively high environmental risks.Various antifouling coatings based on AgNPs have been developed,but there are still some problems.Such as AgNPs are usually easy to agglomerate,AgNPs are not compatible with resins,AgNPs coatings generally have short-acting antifouling properties.In this paper,urushiol,an extracted product from the natural lacquer tree was used as a reducing agent to synthesize AgNPs supported on polyurushiol film(PUL).1.AgNPs were synthesized in one step using silver nitrate as the silver source and urushiol as the reducing agent,and PUL was also formed in the process.Characterization of PUL/AgNPs by HR-TEM,UV-Vis,FT-IR,EDS,XPS and other testing methods.The reaction conditions(urushiol concentration,silver nitrate concentration,reaction temperature,and reaction time)were changed to study the effect of different reaction conditions on the properties of PUL/AgNPs.The results showed that AgNPs have a face-centered cubic crystal structure,and the prepared AgNPs have good dispersibility in PUL.The particle size of AgNPs decreased with the increase of urushiol concentration and reaction temperature,but increased with the increase of silver nitrate concentration and reaction time,respectively.The smallest AgNPs size can be 9.81 nm and the largest size can be 20.8 nm.2.PUL/AgNPs with different AgNPs loading and AgNPs particle size were selected for comparison of antifouling activity.The best performance PUL/AgNPs was selected for further experiments.The experiments showed that the minimum inhibitory concentration(MIC)values of PUL/AgNPs for E.coli and S.aureus were3.125 mg/L and 6.25 mg/L,respectively.The minimum bactericidal concentration(MBC)values for E.coli and S.aureus were 50 mg/L and 70 mg/L,respectively.The lethal concentration of 50%(LC₅₀)of PUL/AgNPs for three algae(I.zhanjiangensis,N.closterium and P.tricornutum)for 24 h were 5.012 mg/L,5.117mg/L,and 6.026 mg/L,respectively.3.One-pot facile method to synthesize PUL/AgNPs(0 wt%,0.05 wt%,0.1wt%,0.3 wt%)into the resin.SEM-mapping results showed that PUL/AgNPs had good dispersion properties in the coatings.Zeta potential results showed that the stability of the composite coating was further improved after the addition of PUL/AgNPs,which proved that AgNPs and resin have good performance,and the stability was highest at 0.1 wt%.Ag⁺ in the coatings can finally achieve stable release,which was a necessary condition for long-term antifouling for coatings.The coatings have good antibacterial effect on E.coli and S.aureus.In addition,the inhibitory effects of the coatings on the three algae were also very good,which showed the PUL/AgNPs coatings have good antifouling ability.