Preparation Of Nano-powder Modified Organic Fluorine-silicone Resin Marine Anti-fouling Coatings

Non-toxic marine antifouling coatings is significant for protecting marineenvironment, and on the basis expanding the antifouling performance will effectivelyachieve unity between antifouling performance enhancement and marine environmentalprotection.In order to prepare excellent low surface energy antifouling coatings, itsbroad-spectrum of antifouling is expanded from three aspects. Firstly, terbinafinehydrochloride（TH） modifing fluorine-silicone resin has been synthesized. Secondly,silicate compound antifouling agent has been self-developed. Thirdly, compound andcladding dispersion of nano powder mixture（TiO₂and SiO₂） have been studied. Finally,the excellent antifouling properties and low toxicity of nano-modified organicfluorine-silicon antifouling marine coatings has been synthesized.The excellent performance silicone-acrylic resin has been selected as the matrix,the broad-spectrum antimicrobial drugs terbinafine hydrochloride has been grafted ontothe chain of silicone-acrylic resin, and following physical blending with thefluorocarbon resin, a new modified organic fluorine-silicone resin has been synthesized.Experimental results shows that organic silicon monomer content contains15%of thetotal monome, the contact angle of the silicone-acrylic resin can achieve88.7°, THmodified silicone-acrylic resin dropps to85.3°, however, the contact angle of THmodified fluorine-silicone resin can reach90°after physical blending the ratio of1:3ofTH modified silicone-acrylic with fluorocarbon resin, it shows that antifoulingperformance has been improved. Inhibition bacteria zone test between modified andunmodified fluorine-silicone resin has also demonstrated that its zone increase from3.2cm to4.5cm, the inhibitory ocean microorganism effect has been enhancedobviously. It indicates that water resistance has been improved by water absorption ratecomparing unmodified fluorine-silicone resin with TH modified one from2.33%reducing to1.23%.Non-toxic silicate compound powder antifouling agents have been developed,their coordination antifouling effect is good as mass ratio selected by the means of theinhibition bacteria zone orthogonal test are sodium silicate:zinc oxide:sulfur:magnesium oxide:zinc30:6:8:8:3.The nano-powder mixture（TiO₂and SiO₂） has also compounded. Suitabledispersants are selected, they can cladded and dispersed nano-powder mixture, and theyare done photocatalytic activity test. The results shows that when blending TiO₂andSiO₂mass ratio is4:1, the inhibitory effect is better. The nano-powder mixture is morestable when adding2.5%titanate TM-P to dispersing solution. LS900laser particle sizeinstrument measuring test also shows that the size of nano-particles cladded anddispersed has been reduced from359nm to38nm, and has still good photocatalyticactivity, photo degradating rate is86.18%, approximately to the original87.49%.The nano-modified organic fluorine-silicon antifouling coatings contains the mainfilm-forming modified organic fluorine-silicone resin, nano-powder mixture（TiO₂andSiO₂）, non-toxic silicate compound antifouling agent and solvent, additive and otherfiller. The optimization formula of the coatings obtained by orthogonal test consists of41wt%modified organic fluorine-silicone resin,5wt%red iron oxide,5wt%talc,5wt%kaolin,5wt%calcium carbonate,2wt%TM-P,28wt%mixed solvent,0.2wt%dispersing agent,0.5wt%defoamer,0.3wt%leveling agent,2wt%nano-powdermixture,6wt%antifouling agent. The contact angle between the coating and water is140.07°. SEM morphology shows that the nano-micron two fold lotus leaf structure isformed on the surface of the coatings, its non-contamination performence has beenimproved obviously.The real sea water suspending test shows that TH modified fluorine-silicone resinwas smaller, antifouling performance is better when the stained area of each panelsmodified and unmodified coatings after two months are contrasted. Addingnano-powder mixture to coatings, the real sea antifouling performance has beenimproved obviously. Nano-powder mixed well, has the better antifouling propertiesthan adding a single species nano-powder, and has the better synergistic antifoulingperformance.Painting film normal performance test shows that gloss of80%, hardness of2B,adhesion force of Class1, impact strength of50kg cm, flexibility of1mm, the film issmooth, the film immersed more than45days by5%salt water is well. Therequirements of low surface energy antifouling coatings has been meeted. Therefore,the coating can be used on ships as a toxic marine antifouling coatings.