| Marine biofouling is a global issue and has adverse effects on human maritime activities.Inthe study of marine biofouling control,silicone-based fouling release coatings have attracted more and more attention because of their eco-friendliness,non-toxicity,and drag-reducing property.However,the drawbacks such as poor mechanical properties,weak adhesion strength,poor antifouling abilities in static condition restrict their development and applications.To solve these problems,self-healing silicone materials with chemically attached amphiphilic telomer were designed in this thesis,with the aim of improving mechanical properties and antifouling abilities of silicone and endowing the silicone with self-healing ability,simultaneously.Furthermore,we also developed self-healable polyurea antifouling materials and studied the relationship between the chemical composition and properties.This thesis aims to study and prepare high-performance marine antifouling materials with good mechanical properties,self-healing properties and antifouling properties,so as to develop multi-functional marine antifouling materials that are environment-adaptive as well as eco-friendly.The main results of research are listed as follows:1)Amphiphilic telomer based on dodecafluoroheptyl methacrylate(DFMA),polyethylene glycol methyl methacrylate(PEGMA)and mercaptopropanediol(TPG)was synthesized through free radical telomerization.Functional chain extender UPy-diol,containing 2-ureido-4[1H]-pyrimidinone(UPy),which can form quadruple hydrogen bonding interaction,was also prepared through two-step reactions.A series of silicone-based polyurethanes were prepared by incorporating the telomer and chain extender into the dihydroxyl terminated poly(dimethylsiloxane)through polyaddition reaction.The adhesion tests on different substrates show that such silicone-based polyurethanes have excellent adhesion strength(0.9-3.0 MPa),which are higher than traditional silicone antifouling materials(0.3-0.4 MPa).The tensile and self-healing tests show that such silicone-based polyurethanes have excellent mechanical properties and self-healing ability and these properties can be tuned by telomer content.When telomer content is up to 15 wt%,such material can be stretched up to 1000%of its original length and self-heal under 25°C for 48 h.The results of contact angle and surface modulus test show that the silicone-based polyurethane coating has low surface energy(24 m J·m-2)and low elastic modulus(1.9 MPa),thus exhibiting good fouling release ability.In addition,the introduction of amphiphilic telomer endows the material with excellent anti-protein,antibacterial and anti-diatom abilities,which significantly improves the fouling resistance of silicone materials.2)Polyether amine T5000 and telomer reacted with isophorone diisocyanate(IPDI)separately to yield prepolymer,then Tri-HDI and 4,4-dithiodiphenylamine(DTDA)curing agent were introduced into the mixture of prepolymer to prepare self-healable antifouling polyurea.The results of adhesion test,tensile tests and macroscopic self-healing test show that such material has good adhesion strength(?1.2 MPa)and tensile strength(?0.3 MPa),the introduction of disulfide bonds makes the polyurea dynamically cross-link,which can improve the healing efficiency.Thus,the material can be stretched up to 5 times its original length after healing at 100°C for 24 h.Water contact angle test shows that the material has hydrophobicity(119°)and low surface energy(?20 m J·m-2).Pseudobarnacle test shows that the material has good fouling release ability(?0.71 MPa).Anti-diatom test demonstrates that the material has excellent anti-diatom property. |
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