Study On Application Of Molecule Self-assembly In Preparation Of Surface Microtopographies Antifouling Materials

Marine biofouling incurs large functional and monetary costs to both vessels and marine facilities. Antifouling coatings are currently the most widespread means of macrofouling prevention, but have harmful effects on the environment and human health. Therefore, the development of no-toxic and "environmentally-friendly" coatings has gained considerable attention. One such class of promising coating alternatives are materials that exhibit a microtopography surface.With organosilicon polymers and acrylate polymers as basic units, this thesis explored three preParation methods of surface microtopography materials according to molecule self-assembly theory. Method 1:physical blending of silane coupling agent modified acrylic resin with silicone resin directly. Due to the phase seParation phenomenon, the mixed resin coating exhibited a microtopography surface after curing by 5% of triethylenetetramine. Moreover, the effects of mixing ratio, R/Si value and viscosity on the size and regularity of the surface microtopographies were discussed. The mixed resin coatings appeared cracking and desquamation phenomenon in the experiment process, which indicated that the coatings were not durable for long term.Method 2:silicone modified acrylic resin was synthesized through the condensation reaction between silicone resin and silane coupling agent modified acrylic resin. All the silicone modified acrylic resins couldn't form regular microtopographies on the coating surface after curing by three different curing agents. Furthermore, due to the Partial hydrolysis of the the methoxy of the silane coupling agent KH-570, the silicone modified acrylic resins were easy to gel and difficult to store.In order to remedy the defects of the two above-mentioned methods, silicone-acrylic copolymer resin was synthesized by acrylate monomers and silicone prepolymer which contained polymeric double bond. The copolymer resin coating surface could exhibit microtopographies after curing by 1% of triethylenetetramine. The Paper also discussed the factors that influenced the size and regularity of the coating surface microtopographies, such as:the proportion of silicone prepolymer and acrylate monomers, the content of acrylonitrile in the acrylate monomers, the R/Si value and viscosity of silicone prepolymer. And the seawater immersion experiment showed that the copolymer resin coatings were adaptive to long-term seawater immersion entironment.The coating surface microtopographies formation mechanism of silicone-acrylic copolymer resin was also studied. The directional-migration of polarity and nonpolarity chain segments made the coating surface to exhibit porous structure as the silicone component as the core.The antifouling performance testing showed that the size of the coating surface microtopographies had significant effect on the settlement of the diatoms and zoospores. Furthermore, the presence of microtopographies effectively reduced the attachment points of the diatoms and zoospores, consequently, the fouling organisms were easy to be removed under external force and the removing rates were almost above 85%. Also, the inhibition effect of mussel attachment was improved on the microtopography coating surface.According to the molecule self-assembly theory, this thesis explored three preParation methods of surface microtopography materials with organosilicon polymers and acrylate polymers as basic units. In order to apply the surface microtopography materials into the marine antifouling field, we have still many problems which need further-more overcome.