Antifouling coatings are used extensively on vessels and underwater structures. Conventional antifouling coatings contain toxic biocides and heavy metals, which may induce unwanted adverse effects such as toxicity to ...Antifouling coatings are used extensively on vessels and underwater structures. Conventional antifouling coatings contain toxic biocides and heavy metals, which may induce unwanted adverse effects such as toxicity to non-target organisms, imposex in gastropods and increased multiresistance among bacteria. Therefore,enzyme-based coatings could be a new alternative solution. A H2O2-producing bienzyme system was developed in this study. H2O2 can be produced from starch by the cooperation of α-amylase and glucose oxidase, which promotes the hydrolysis of polymeric chain and oxidizes the glucose to produce H2O2, respectively. The encapsulated bienzyme(A-G@BS) exhibits enhanced stabilities of thermal, pH, recycling and tolerance of xylene. The A-G@BScontaining coating releases H2O2 at rates exceeding a target of 36 nmol·cm-2·d-1for 90 days in a laboratory assay. The results demonstrate that the method is a promising coating technology for entrapping active enzymes,presenting an interesting avenue for enzyme-based antifouling solutions.展开更多
Enzyme-based antifouling coatings are potential alternative to traditional tributyltin-based coatings in the marine biofouling control depended on its environmental friendliness.Proteases are usually the key antifouli...Enzyme-based antifouling coatings are potential alternative to traditional tributyltin-based coatings in the marine biofouling control depended on its environmental friendliness.Proteases are usually the key antifouling active components in enzyme based antifouling coatings.In this work,based on biological antagonism effect,a marine proteolytic bacterial strain of Bacillus velezensis was isolated from the sea mud,and denoted as SM-1.The scanning electron microscope(SEM)revealed that the bacteria are rod-shaped with length 1-1.3μm.The protease-producing conditions of SM-1 were investigated,and it was found that the culture solution displays higher proteolytic activity under the culture conditions of 35℃,10‰-20‰salinity,pH 6-9 and more than 7 d culture time.Moreover,the 25 kDa protein was confirmed to be the main active component in the crude protease,which was revealed via the experiment of SDS-PAGE.The antifouling assay indicated that the protease SM-1 has remarkable effect on the decomposition of barnacle cement and diatom secretion,and also can effectively inhibit the attachment of barnacle cyprids,diatom and mussel byssus.Therefore,this protease potentially can be used as environmental-friendly antifoulant of enzyme-based marine antifouling coatings,and this work also provides a new approach to obtain antifouling protease via isolating proteolytic bacteria from the sea mud surrounding representative fouling organisms.展开更多
All antifouling paints in use today are effective because toxic ingredients based on heavy metals are included in their formulation, the environmental effects of organotins in seawater have been a topic of much intere...All antifouling paints in use today are effective because toxic ingredients based on heavy metals are included in their formulation, the environmental effects of organotins in seawater have been a topic of much interest and concern in recent years. This study has found that the material of rich silicone rubber on coating surface based on the low discursive component of surface energy makes barnacle settling on them unable to attach permanently and is removed by moving water. The material Permits only small amounts of fouling to attach, such as algae, Ciona intestinalis, because the high polar interaction of coating surface may absorb water to form water film in sea, and cause very low adhesion of the fouling spotes.展开更多
Traditional antifouling agents usually have a certain toxic effect on marine environments and non-target organisms.In this study,Dictyophora indusiata polysaccharide(DIP)was applied as a natural antifouling surface mo...Traditional antifouling agents usually have a certain toxic effect on marine environments and non-target organisms.In this study,Dictyophora indusiata polysaccharide(DIP)was applied as a natural antifouling surface modifier to prepare the surface coating for marine antifouling.Three DIP coatings were prepared:D.indusiata spore polysaccharide(DISP),D.indusiata volva polysaccharide(DIVP),and D.indusiata embryonic body polysaccharide(DIEP).The antifouling,tribological,and anticorrosion behavior of the coatings were examined.Results revealed that the three kinds of DIP coatings had excellent antifouling properties,which could effectively prevent the adhesion of Chlorella and the attachment of water-based and oily stains on the surface.Additionally,the coatings showed great mechanical stability and could maintain an extremely low coefficient of friction(COF<0.05)after continuous wear.The drag reduction rate of the coated surfaces reached 5%,showing a powerful lubrication performance.Furthermore,the DIP coatings presented an outstanding corrosion resistance,where the equivalent circuit impedances were 4-9 orders of magnitude higher than the control groups.This research showed a promising prospect of surface coating fabrication with DIP for marine devices to achieve the purpose of antifouling and drag reduction.展开更多
Zwitterion-based materials by virtue of their special physical and chemical characteristics have attracted researchers to utilize them for fabricating functional coatings. The simultaneous presence of positive and neg...Zwitterion-based materials by virtue of their special physical and chemical characteristics have attracted researchers to utilize them for fabricating functional coatings. The simultaneous presence of positive and negative charges renders the zwitterion-based materials with electrostatically induced hydration properties, which enables a high resistance towards oily pollutants, nonspecific protein adsorption, bacterial adhesion and biofilm formation. This review starts from the working mechanism of zwitterions and covers the fabrication strategies of zwitterion-based functional coatings, namely the zwitterion-bearing binder route, the zwitterion-bearing additive route and the post-generation of coatings containing zwitterionic precursors. The applications of zwitterion-based functional coatings are discussed, including medical implants, marine antifouling and oil-resistant coatings, with focus on the relevant mechanisms of the zwitterion-containing coatings for a specific performance. Finally, some comments and perspectives on the current situation and future development of zwitterion-based functional coatings are given.展开更多
This paper summarizes a nontoxic Anti-fouling coating utilizing capsaicin as an anti-fouling agent. The capsaicin constituent used in the coating has a rating from about 100 000 to about 1 500 000 Scoville Heat Units....This paper summarizes a nontoxic Anti-fouling coating utilizing capsaicin as an anti-fouling agent. The capsaicin constituent used in the coating has a rating from about 100 000 to about 1 500 000 Scoville Heat Units. The capsaicin is mixed with a silicon dioxide and then solubilized into a free-flowing homogeneous liquid oleoresin composition by adding a solvent to increase solubility and facilitate mixing. The oleoresin capsaicin liquid solution is mixed with a suitable corrosion resistant epoxy resin, which is then mixed with a hardening catalyst and applied to the surface to be treated.展开更多
Antifouling coatings are used to improve the speed and energy efficiency of ships by preventing or- ganisms, such as barnacles and weed, building up on the underwater hull and helping the ships movement through the wa...Antifouling coatings are used to improve the speed and energy efficiency of ships by preventing or- ganisms, such as barnacles and weed, building up on the underwater hull and helping the ships movement through the water. Typically, marine coatings are tributyltin self-polishing copolymer paints containing toxic molecules called biocides. They have been the most successful in combating bio- fouling on ships, but their widespread use has caused severe pollution in the marine ecosystem. The low surface energy marine coating is an entirely non-toxic alternative, which reduces the adhesion strength of marine organisms, facilitating their hydrodynamic removal at high speeds. In this paper, the novel low surface energy non-toxic marine antifouling coatings were prepared with modified acrylic resin, nano-SiO2, and other pigments. The effects of nano-SiO2 on the surface structure and elastic modulus of coating films have been studied, and the seawater test has been carried out in the Dalian Bay. The results showed that micro-nano layered structures on the coating films and the lowest surface energy and elastic modulus could be obtained when an appropriate mass ratio of resin, nano-SiO2, and other pigments in coatings approached. The seawater exposure test has shown that the lower the sur- face energy and elastic modulus of coatings are, the less the marine biofouling adheres on the coating films.展开更多
Using natural product-based antifouling coatings has proven to be an effective strategy to combat biofouling.However,their antifouling mechanisms are still unclear.In this study,the antifouling mechanism of natural pr...Using natural product-based antifouling coatings has proven to be an effective strategy to combat biofouling.However,their antifouling mechanisms are still unclear.In this study,the antifouling mechanism of natural product-based coatings consisting of bio-sourced poly(lactic acid)-based polyurethane and ecofriendly antifoulant(butenolide)derived from marine bacteria was revealed by observing 3D bacterial motions utilizing a 3D tracking technique-digital holographic microscopy(DHM).As butenolide content increases,the density of planktonic marine bacteria(Pseudomonas sp.)near the surface decreases and thus leads to a reduced adhesion,indicating that butenolide elicits the adaptive response of Pseudomonas sp.to escape from the surface.Meanwhile,among these remained cells,an increased percentage is found to undergo subdiffusive motions compared with the case of smaller dose of butenolide.Further experiments show that butenolide can accelerate their swimming velocity and reduce flick frequency.Antibacterial assay confirms that butenolide-based coating shows high efficacy of antifouling performance against Pseudomonas sp.but without killing them like 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one(DCOIT).展开更多
Marine fouling is a worldwide challenge with huge damages on industrial structures,side effects on economics of industries,and environmental and safety-related hazards.Different approaches have been used for combating...Marine fouling is a worldwide challenge with huge damages on industrial structures,side effects on economics of industries,and environmental and safety-related hazards.Different approaches have been used for combating fouling in the marine environment.Meanwhile,nanocomposite polymer coatings are a novel generation of antifouling coatings with merits of toxin-free chemical composition and ease of large-scale application.Nanomaterials such as nano-metals,nano-metal oxides,metal-organic frameworks,carbon-based nanostructures,MXene,and nanoclays have antibacterial and antifouling properties in the polymer coatings.Besides,these nanomaterials can improve the corrosion resistance,mechanical strength,weathering stability,and thermal resistance of the polymer coatings.Therefore,in this review paper,the antifouling nanocomposite coatings are introduced and antifouling mechanisms are discussed.This review explicitly indicates that the antifouling efficiency of the nanocomposite coatings depends on the properties of the polymer matrix,the inherent properties of the nanomaterials,the weight percent and the dispersion method of the nanomaterials within the coating matrix,and the chemicals used for modifying the surface of the nanomaterials;meanwhile,the hybrids of different nanomaterials and appropriate chemical agents could be used to improve the antifouling behavior of the prepared nanocomposites.Moreover,the theoretical studies are introduced to pave the way of researchers working on theantifouling coatings,and the importance of the theoretical studies and computational modeling along with the experimental research is notified to develop antifouling coatings with high efficiency.展开更多
Hydrophilic modification is a promising method to inhibit fouling formation on ultrafiltration membrane.In this work,different mass concentrations(1%–16%)of hydrophilic polyvinylpyrrolidone were incorporated into pol...Hydrophilic modification is a promising method to inhibit fouling formation on ultrafiltration membrane.In this work,different mass concentrations(1%–16%)of hydrophilic polyvinylpyrrolidone were incorporated into polyethersulfone(PES)membranes fabricated by none-solvent induced phase separation.Then,polydopamine(PDA)coating on the surface of prepared membrane was carried out at pH 8.5.The morphology and structure,surface hydrophilicity,permeation flux,BSA rejection,antifouling and stability performances of PES and PDA/PES modified membranes were investigated in detail.The results indicated that PDA was successfully attached onto the membranes.Membrane hydrophilicity was evaluated by water contact angle measurement.The contact angles of modified membranes reduced remarkably,suggesting that the membrane hydrophilicities were significantly increased.The results of filtration tests,which were done by dead-end filtration of bovine serum albumin solution,showed that the properties of permeability and fouling resistance were obviously improved by PDA modification.When polyvinylpyrrolidone mass content reached 10%,flux recovery ratio of modified membrane was up to91.23%,and its BSA rejection were over 70%.The results of stability tests showed that the modified membranes had good mechanical stability and chemical stability.This facile fabrication procedure and outstanding performances suggested that the modified membranes had a potential in treating fouling.展开更多
Simultaneous realization of superior mechanical and antifouling properties is critical for a coating. The use of stereoscopic polysiloxanes in place of linear polysiloxanes to fabricate antifouling coatings can combin...Simultaneous realization of superior mechanical and antifouling properties is critical for a coating. The use of stereoscopic polysiloxanes in place of linear polysiloxanes to fabricate antifouling coatings can combine properties of organic and inorganic materials, i.e., they can exhibit both high hardness and wear resistance from inorganic components as well as the flexibility and tunability from organic components. This strategy is used to prepare hard yet flexible antifouling coatings or polymer-ceramic hybrid antifouling coatings. In this mini-review, we report the recent advances in this field. Particularly, the effects of stereoscopic polysiloxane structures on their mechanical and antifouling properties are discussed in detail.展开更多
基金Supported by the National Natural Science Foundation of China(21006020,21276060,21276062)the Application Basic Research Plan Key Basic Research Project of Hebei Province(11965150D)the Natural Science Foundation of Tianjin(13JCYBJC18500)
文摘Antifouling coatings are used extensively on vessels and underwater structures. Conventional antifouling coatings contain toxic biocides and heavy metals, which may induce unwanted adverse effects such as toxicity to non-target organisms, imposex in gastropods and increased multiresistance among bacteria. Therefore,enzyme-based coatings could be a new alternative solution. A H2O2-producing bienzyme system was developed in this study. H2O2 can be produced from starch by the cooperation of α-amylase and glucose oxidase, which promotes the hydrolysis of polymeric chain and oxidizes the glucose to produce H2O2, respectively. The encapsulated bienzyme(A-G@BS) exhibits enhanced stabilities of thermal, pH, recycling and tolerance of xylene. The A-G@BScontaining coating releases H2O2 at rates exceeding a target of 36 nmol·cm-2·d-1for 90 days in a laboratory assay. The results demonstrate that the method is a promising coating technology for entrapping active enzymes,presenting an interesting avenue for enzyme-based antifouling solutions.
基金supported by the National Basic Research Program of China (No. 2014CB643305)the National Natural Science Foundation of China (No. 213 01161)
文摘Enzyme-based antifouling coatings are potential alternative to traditional tributyltin-based coatings in the marine biofouling control depended on its environmental friendliness.Proteases are usually the key antifouling active components in enzyme based antifouling coatings.In this work,based on biological antagonism effect,a marine proteolytic bacterial strain of Bacillus velezensis was isolated from the sea mud,and denoted as SM-1.The scanning electron microscope(SEM)revealed that the bacteria are rod-shaped with length 1-1.3μm.The protease-producing conditions of SM-1 were investigated,and it was found that the culture solution displays higher proteolytic activity under the culture conditions of 35℃,10‰-20‰salinity,pH 6-9 and more than 7 d culture time.Moreover,the 25 kDa protein was confirmed to be the main active component in the crude protease,which was revealed via the experiment of SDS-PAGE.The antifouling assay indicated that the protease SM-1 has remarkable effect on the decomposition of barnacle cement and diatom secretion,and also can effectively inhibit the attachment of barnacle cyprids,diatom and mussel byssus.Therefore,this protease potentially can be used as environmental-friendly antifoulant of enzyme-based marine antifouling coatings,and this work also provides a new approach to obtain antifouling protease via isolating proteolytic bacteria from the sea mud surrounding representative fouling organisms.
文摘All antifouling paints in use today are effective because toxic ingredients based on heavy metals are included in their formulation, the environmental effects of organotins in seawater have been a topic of much interest and concern in recent years. This study has found that the material of rich silicone rubber on coating surface based on the low discursive component of surface energy makes barnacle settling on them unable to attach permanently and is removed by moving water. The material Permits only small amounts of fouling to attach, such as algae, Ciona intestinalis, because the high polar interaction of coating surface may absorb water to form water film in sea, and cause very low adhesion of the fouling spotes.
基金National Natural Science Foundation of China(52375298,51975458,and 51905370)support from the China Scholarship Council,China Postdoctoral Science Foundation funded project(2020M673377 and 2020T130510)+1 种基金Key R&D program of Shaanxi Province(2022SF-069)the Natural Science Fund of Shaanxi Province(2020JM-010).
文摘Traditional antifouling agents usually have a certain toxic effect on marine environments and non-target organisms.In this study,Dictyophora indusiata polysaccharide(DIP)was applied as a natural antifouling surface modifier to prepare the surface coating for marine antifouling.Three DIP coatings were prepared:D.indusiata spore polysaccharide(DISP),D.indusiata volva polysaccharide(DIVP),and D.indusiata embryonic body polysaccharide(DIEP).The antifouling,tribological,and anticorrosion behavior of the coatings were examined.Results revealed that the three kinds of DIP coatings had excellent antifouling properties,which could effectively prevent the adhesion of Chlorella and the attachment of water-based and oily stains on the surface.Additionally,the coatings showed great mechanical stability and could maintain an extremely low coefficient of friction(COF<0.05)after continuous wear.The drag reduction rate of the coated surfaces reached 5%,showing a powerful lubrication performance.Furthermore,the DIP coatings presented an outstanding corrosion resistance,where the equivalent circuit impedances were 4-9 orders of magnitude higher than the control groups.This research showed a promising prospect of surface coating fabrication with DIP for marine devices to achieve the purpose of antifouling and drag reduction.
基金Sponsored by the National Key Research and Development Program of China(Grant No.2020YFE0100300)the National Natural Science Foundation of China(Grant No.51973036)。
文摘Zwitterion-based materials by virtue of their special physical and chemical characteristics have attracted researchers to utilize them for fabricating functional coatings. The simultaneous presence of positive and negative charges renders the zwitterion-based materials with electrostatically induced hydration properties, which enables a high resistance towards oily pollutants, nonspecific protein adsorption, bacterial adhesion and biofilm formation. This review starts from the working mechanism of zwitterions and covers the fabrication strategies of zwitterion-based functional coatings, namely the zwitterion-bearing binder route, the zwitterion-bearing additive route and the post-generation of coatings containing zwitterionic precursors. The applications of zwitterion-based functional coatings are discussed, including medical implants, marine antifouling and oil-resistant coatings, with focus on the relevant mechanisms of the zwitterion-containing coatings for a specific performance. Finally, some comments and perspectives on the current situation and future development of zwitterion-based functional coatings are given.
文摘This paper summarizes a nontoxic Anti-fouling coating utilizing capsaicin as an anti-fouling agent. The capsaicin constituent used in the coating has a rating from about 100 000 to about 1 500 000 Scoville Heat Units. The capsaicin is mixed with a silicon dioxide and then solubilized into a free-flowing homogeneous liquid oleoresin composition by adding a solvent to increase solubility and facilitate mixing. The oleoresin capsaicin liquid solution is mixed with a suitable corrosion resistant epoxy resin, which is then mixed with a hardening catalyst and applied to the surface to be treated.
基金High-Tech Research and Development Program of China (Grant No. 2004AA001520)
文摘Antifouling coatings are used to improve the speed and energy efficiency of ships by preventing or- ganisms, such as barnacles and weed, building up on the underwater hull and helping the ships movement through the water. Typically, marine coatings are tributyltin self-polishing copolymer paints containing toxic molecules called biocides. They have been the most successful in combating bio- fouling on ships, but their widespread use has caused severe pollution in the marine ecosystem. The low surface energy marine coating is an entirely non-toxic alternative, which reduces the adhesion strength of marine organisms, facilitating their hydrodynamic removal at high speeds. In this paper, the novel low surface energy non-toxic marine antifouling coatings were prepared with modified acrylic resin, nano-SiO2, and other pigments. The effects of nano-SiO2 on the surface structure and elastic modulus of coating films have been studied, and the seawater test has been carried out in the Dalian Bay. The results showed that micro-nano layered structures on the coating films and the lowest surface energy and elastic modulus could be obtained when an appropriate mass ratio of resin, nano-SiO2, and other pigments in coatings approached. The seawater exposure test has shown that the lower the sur- face energy and elastic modulus of coatings are, the less the marine biofouling adheres on the coating films.
基金financially supported by the National Natural Science Foundation of China(Nos.51673074,21973032 and 21637001)the Fundamental Research Funds for the Central Universities(No.2019ZD02)the Fund of the Key Laboratory of Luminescence from Molecular Aggregates of Guangdong Province(No.2019B030301003)。
文摘Using natural product-based antifouling coatings has proven to be an effective strategy to combat biofouling.However,their antifouling mechanisms are still unclear.In this study,the antifouling mechanism of natural product-based coatings consisting of bio-sourced poly(lactic acid)-based polyurethane and ecofriendly antifoulant(butenolide)derived from marine bacteria was revealed by observing 3D bacterial motions utilizing a 3D tracking technique-digital holographic microscopy(DHM).As butenolide content increases,the density of planktonic marine bacteria(Pseudomonas sp.)near the surface decreases and thus leads to a reduced adhesion,indicating that butenolide elicits the adaptive response of Pseudomonas sp.to escape from the surface.Meanwhile,among these remained cells,an increased percentage is found to undergo subdiffusive motions compared with the case of smaller dose of butenolide.Further experiments show that butenolide can accelerate their swimming velocity and reduce flick frequency.Antibacterial assay confirms that butenolide-based coating shows high efficacy of antifouling performance against Pseudomonas sp.but without killing them like 4,5-dichloro-2-n-octyl-4-isothiazolin-3-one(DCOIT).
基金supported financially by the CAS President’s International Fellowship Initiative 2019(PIFI,No.2019PE0059)CAS-VPST Silk Road Science Fund 2021(133137KYSB20200034)INSF’s Project No.99010368。
文摘Marine fouling is a worldwide challenge with huge damages on industrial structures,side effects on economics of industries,and environmental and safety-related hazards.Different approaches have been used for combating fouling in the marine environment.Meanwhile,nanocomposite polymer coatings are a novel generation of antifouling coatings with merits of toxin-free chemical composition and ease of large-scale application.Nanomaterials such as nano-metals,nano-metal oxides,metal-organic frameworks,carbon-based nanostructures,MXene,and nanoclays have antibacterial and antifouling properties in the polymer coatings.Besides,these nanomaterials can improve the corrosion resistance,mechanical strength,weathering stability,and thermal resistance of the polymer coatings.Therefore,in this review paper,the antifouling nanocomposite coatings are introduced and antifouling mechanisms are discussed.This review explicitly indicates that the antifouling efficiency of the nanocomposite coatings depends on the properties of the polymer matrix,the inherent properties of the nanomaterials,the weight percent and the dispersion method of the nanomaterials within the coating matrix,and the chemicals used for modifying the surface of the nanomaterials;meanwhile,the hybrids of different nanomaterials and appropriate chemical agents could be used to improve the antifouling behavior of the prepared nanocomposites.Moreover,the theoretical studies are introduced to pave the way of researchers working on theantifouling coatings,and the importance of the theoretical studies and computational modeling along with the experimental research is notified to develop antifouling coatings with high efficiency.
基金supported by the National Natural Science Foundation of China(Nos.51573041,21776067)the Demonstration Base Project of University-Enterprise Cooperation of Hunan Province(No.145812)。
文摘Hydrophilic modification is a promising method to inhibit fouling formation on ultrafiltration membrane.In this work,different mass concentrations(1%–16%)of hydrophilic polyvinylpyrrolidone were incorporated into polyethersulfone(PES)membranes fabricated by none-solvent induced phase separation.Then,polydopamine(PDA)coating on the surface of prepared membrane was carried out at pH 8.5.The morphology and structure,surface hydrophilicity,permeation flux,BSA rejection,antifouling and stability performances of PES and PDA/PES modified membranes were investigated in detail.The results indicated that PDA was successfully attached onto the membranes.Membrane hydrophilicity was evaluated by water contact angle measurement.The contact angles of modified membranes reduced remarkably,suggesting that the membrane hydrophilicities were significantly increased.The results of filtration tests,which were done by dead-end filtration of bovine serum albumin solution,showed that the properties of permeability and fouling resistance were obviously improved by PDA modification.When polyvinylpyrrolidone mass content reached 10%,flux recovery ratio of modified membrane was up to91.23%,and its BSA rejection were over 70%.The results of stability tests showed that the modified membranes had good mechanical stability and chemical stability.This facile fabrication procedure and outstanding performances suggested that the modified membranes had a potential in treating fouling.
基金supported by the National Natural Science Foundation of China(Nos.52273073,U2241286 and 52003082)National Key Research and Development Program of China(No.2022YFB3806403)Fundamental Research Funds for the Central Universities.
文摘Simultaneous realization of superior mechanical and antifouling properties is critical for a coating. The use of stereoscopic polysiloxanes in place of linear polysiloxanes to fabricate antifouling coatings can combine properties of organic and inorganic materials, i.e., they can exhibit both high hardness and wear resistance from inorganic components as well as the flexibility and tunability from organic components. This strategy is used to prepare hard yet flexible antifouling coatings or polymer-ceramic hybrid antifouling coatings. In this mini-review, we report the recent advances in this field. Particularly, the effects of stereoscopic polysiloxane structures on their mechanical and antifouling properties are discussed in detail.