| Fixed equipment and ships in the ocean are vulnerable to the formation of biofouling by the undesirable settlement and attachment growth of algae,shellfish and other polluting organisms,which will not only affect the operation of equipment[1],but also reduce the service life of equipment and cause adverse ecological and economic impacts.Applying antifouling coating is the most convenient and effective way to prevent biological pollution.Traditional organotin-based antifouling materials contain heavy metal components,and their long-term use seriously damages the marine ecological environment,so the development of efficient and environmentally friendly antifouling materials has become an urgent need in the field of marine antifouling.At present,the mainstream green antifouling materials include self-polishing type,low surface energy type,biodegradable type and bionic type antifouling materials.Polyurethane（PU）is widely used in the field of coatings because of its excellent mechanical properties and adjustable performance and controllable molecular structure.In this thesis,two environmentally friendly polyurethane marine antifouling materials were prepared according to different antifouling mechanisms,respectively,as follows:（1）Preparation and performance study of PCLU/HNTs-TCPM marine antifouling composites:using halloysite（HNTs）with high aspect ratio and hollow lumen structure as a carrier to load the environmentally friendly antifouling agent N-（2,4,6-trichlorophenyl）maleimide（TCPM）to make a slow-release filler（HNTs-TCPM）,exploring the best experimental parameters to achieve a loading rate of The poly（caprolactone-based degradable polyurethane）（PCLU）materials were prepared by using poly（caprolactone）（PCL-diol）as the soft segment and 4,4’-dicyclohexylmethane diisocyanate（HMDI）and 1,4-butanediol（BDO）as the hard segment with double hydroxyl capping,and static hydrolysis experiments showed that the hydrolysis performance of PCLU increased and then decreased with the increase of PCL content;combining HNTs-TCPM and PCLU were blended to prepare PCLU/HNTs-TCPM degradable antifouling composites.The experimental results showed that the introduction of HNTs significantly reduced the crystallinity of PCLU.UV-vis analysis showed that the PCLU/HNTs-TCPM composites could release TCPM continuously at a low level rate,and the release of TCPM was only 16.5%of the total load in 5 months,which was 2.8 times lower compared with PCLU/TCPM.Antibacterial experiments showed that the PCLU/HNTs-TCPM composites were still bacterially effective after 60 days of immersion in artificial seawater.（2）Preparation and performance study of FPCLU marine antifouling material:3-Mercapto-1,2-propanediol（TPG）and perfluoroalkyl ethyl methacrylate（FDMA）were prepared as fluorinated diol chain extender FDMA（OH）2 by click reaction,which was used in the synthesis of polyurethane to prepare fluorinated polyurethane（FPCLU）with low surface energy.The experimental results showed that FDMA was successfully introduced into FPCLU,and the fluorinated groups migrated to the surface of FPCLU and were enriched.Thermogravimetric analysis showed that the incorporation of FDMA side groups improved the thermal stability of FPCLU,and the T95%increased from 366°C to 432°C with the increase of side group content.And with the increase of FDMA content,the water contact angle of FPCLU increased from70°to 105°,and hydrophobicity was significantly enhanced,while the surface energy was reduced from 36.81 m J/m2 to 16.58 m J/m2.bacterial adhesion test showed that FPCLU could significantly reduce the adhesion of sodium-demanding Vibrio vulnificus compared with PCLU.This material provides a simple and effective preparation solution for the application of fluorinated polyurethane in the field of marine antifouling,and has the potential to be applied as a marine antifouling material. |
