Preparation And Antifouling Properties Of Indole Derivative Modified Fluorinated/boron Acrylate Copolymers

In the development and utilization of marine resources,the artificial facilities such as ships and offshore platforms in the ever-changing marine environment have encountered various problems.Among them,the fouling of marine organisms caused by the adhesion of marine organisms on the surface of the facility is one of the current difficulties.The currently widely used marine antifouling coatings kill fouling organisms by releasing antifouling agents such as cuprous oxide,and they have a greater negative impact on the marine environment.Therefore,the development of environment-friendly antifouling coatings has become a hot issue in marine antifouling.In this paper,indole derivative modified fluorinated/ boron acrylate composite coatings were prepared by introducing indole derivatives into fluorinated/ boron acrylate polymers through chemical grafting,random copolymerization and filler functionalization.The structure of indole derivative modified fluorinated/ boron acrylate copolymers and fillers were characterized.The surface properties,self-polishing rate and environmental friendliness of the coatings were investigated,and the antifouling performance of coatings were evaluated by anti-bacterial,anti-diatonsettled adhesion and real sea static suspension experiments.Acrylate fluorinated polymers containing epoxy groups in the side chain were prepared by radical polymerization of monomers such as hexafluorobutyl methacrylate and glycidyl methacrylate.Indole derivative modified acrylate fluorinated polymer(AFIP)was prepared by grafting indole acetic acid on the side chain of acrylate fluorinated polymer by nucleophilic ring-opening reaction of epoxy group and amino group.The wettability of the AFIP polymer coatings were tested,and it was found that the addition of fluorinated monomer increased the water contact angle of the coating surface.The surface morphology of AFIP coatings were observed and the water resistance of AFIP coatings were tested,it was found that compared with the coatings without fluorinated monomer,the surface of the AFIP coatings did not crack after being immersed in sea water.It showed that fluorinated monomer can enhance the water resistance of the coatings.Through toxicity experiments.It was found that the coatings containing indole acetic acid had no effect on the growth activity of Nitzschia closterium f.minutissima in the algae liquid,and the AFIP coatings is environment-friendly.Through antibacterial,anti-diatonsettled adhesion and real sea static suspension tests,it was found that indole acetic acid can enhance the inhibitory activity of the coatings against fouling organisms.The AFIP coatings had a maximum antibacterial ratio of 93.5% against Escherichia coli,and a maximum anti-diatonsettled ratio of 97.43%against Phaeodactylum tricornutum.The surface of the AFIP coating with 15% mass fraction of indole acetic acid had little fouling and biological adhesion after being immersed in the ocean for 90 days.Acrylate indole modified acrylate boron polymers(ABIP)were prepared by copolymerizing acrylate indole monomer into the main chain of acrylate ester polymers by free radical polymerization,and grafting pyridine triphenylborane(TPBP)into the side chain of the polymers through proton exchange reaction.Compared with AFIP polymer coatings,ABIP polymer coatings have self-polishing properties.With the increase of acrylate indole monomer,the self-polishing rate of the coatings gradually increases.Through anti-bacterial and anti-diatonsettled adhesion experiments,it was found that as the mass fraction of acrylate indole in the coating increases,the inhibitory activity of the coating on bacteria and diatoms increased.Compared with AFIP polymer coatings,ABIP polymer coatings had higher inhibitory activity against Staphylococcus aureus,and its anti-bacterial ratio had reached 98.44%.Through the real sea static suspension experiments,it was found that the ABIP coatings with 8% acrylate indole mass fraction had the best real sea antifouling performance.Acrylate fluorinated polymers were prepared by copolymerizing hexafluorobutyl methacrylate in the polymer main chain by free radical polymerization.And acrylate fluorinated boron polymers(AFBP)were prepared by grafting TPBP on the side chain of acrylate fluorinated using proton exchange reaction.Graphene oxide(GO)was prepared by the improved Hummers method.Polyindole modified GO(PGO)was prepared by in-situ chemical oxidation.Polyindole was coated on the surface of GO.PGO was dispersed in AFBP to prepare polyindole modified graphene oxide/acrylate fluorinated boron composite antifouling coatings(PGO/AFBP).The surface properties of the PGO/AFBP composite coatings had been characterized and found that as the mass fraction of PGO fillers in the coating increase,the water contact angle of the coating surface first increases and then decreases.The self-polishing rate of the coatings were tested,and it was found that the introduction of hydrophobic PGO nano fillers can control the self-polishing rate of the composite coatings.When the mass fraction of PGO in the composite coatings were 0.5% and 0.7%,the weight loss rate after immersing in artificial sea water for 20 days was 5.1% and 3.1%.The toxicity of the composite coating was evaluated,and it was found that the composite coating with a PGO mass fraction of 0.7% had the least toxicity to Nitzschia closterium f.minutissima in the algae liquid.Through anti-bacterial and anti-diatonsettled adhesion experiments,the composite coating with a PGO mass fraction of 0.5% had an anti-diatonsettled ratio of 96.55% against Halamphora sp.,which has the strongest adhesion force,and an anti-bacterial ratio of 97.3% against Staphylococcus aureus.