| Fluorocarbons with long perfluoroalkyl chain (CnF2n+1, n≥8) were widely used as water and oil repellent due to their outstanding low surface free energy. However, there are increasing evidences for bioaccumulation and/or toxicity of compounds containing the long perfluoroalkyl chains. Environmental benign finishing reagents containing short fluorocarbon chains (CnF2n+1, n≤6) are highly regarded in recent decade, whereas its oleophobicity is still undesirable. Perfluoropolyether (PFPE) seem to be the promising substitute for long-chain perfluoroalkane due to their excellent physical and chemical properties such as high chemical resistance, high lubricating ability, low surface energy and low toxicity.In this study, on the basis of the theory for hydrophobic/oleophobic solid surface, we used 2,3,3,3-tetrafluoro-2-(1,1,2,3,3,3-hexafluoro-2-(perfluoropropoxy)propoxy)propanoyl fluoride (THPF) as fluorine-containing monomer to synthesize several classes of hybrid fluorine-and silicon-containing polymers and applied the polymers as surface modifying agents on cotton fabrics. Wetting properties of the treated cotton fabrics were measured. The main work is described as follows:(1) Four types of silica grafted with PFPE (RrSiO2-1, Rf-Si02-2, Rf-Si02-3(1) and RrSi02-3(2)) were prepared. Hybrid material Rf-SiO2-3(2) with micro-nano scale binary structure (MNBS) achieved superhydrophobicity and highly oleophobicity. The chemical composite and surface micromorphology of the hybrid materials were characterized by FT-IR, XPS,SEM,AFM and element analysis. Nano SiO2 was prepared by sol-gel method in alkaline condition. Factors affecting the size of the nano SiO2 were investigated. Preparation of amino SiO2 (APES-SiO2) and the effects of the amidation reaction on hydrophobicity and oleophobicity of the hybrid materials were also studied. It was found that the reaction time for preparing the fluorinated silica from amino nano-silica and THPF plays an important role in water and oil repellency of the coated surface. On the surface of glass substrate coated with RrSi02-3(2), water contact angle could achieve 157°, while for n-tetradecane and n-dodecane contact angle,132°and 113°, respectively. Thermogravimetric analysis showed that the onset decomposition temperature of RrSiO2-3(2) was more than 200℃and the maximum decomposition rate temperature was more than 300℃, which was suitable for common application such as construction coating and textile finishing. The wetting properties of the cotton fabrics changed greatly before and after treated with RrSiO2-3(2)/PMMA blend. Hydrophobicity and oleophobicity of the treated cotton fabrics could be improved by increasing the content of RrSiO2-3(2).(2) Four kinds of hydrophobic and oleophobic treated cotton fabrics (S1, S2, S3 and S4) were prepared. The superhydrophobic and highly oleophobic cotton fabrics S3 and S4 were obtained by applying particle-based in situ fabrication procedure with two synthesized fluorinating agent and the silica particles precursor tetraethyl orthosilicate (TEOS). The effects of SiO2 particle size and TEOS dosage during in situ procedure on the hydrophobicity of the treated cotton fabrics were investigated. The chemical composite of the synthesized fluorinating agents were characterized by FT-IR and NMR. The surface composite and micromorphology of the treated cotton fabrics were analyzed by XPS and SEM. The results showed that introduction PFPE chains into cotton fabrics with micro/sub-micro surface structure could improve hydrophobicity and oleophobicity greatly. Compared with S3, S4 is possessed of higher water and oil repellency. The water and salad oil contact angle on S4 surface could achieve 160°,146°respectively, moreover, water and oil repellency ratings were 90 and 4.(3) The core-shell polyacrylate emulsion (FSP) containing perfluoropolyether (PFPE) in the shell and 3-(methacryloxy) propyltrimethoxy silane modified nano-silica in the core was synthesized by semi-continuous seeded emulsion polymerization in the presence of anion/nonionic emulsifier. Environmental friendly fatty alcohol-polyoxyethylene ether was applied as nonionic emulsifier rather than alkylphenol ethoxylates which are harm to human and environment. The effects of the HLB value of the anion/nonionic emulsifier on the emulsion were studied, as well as the effects of emulsifier dosage, initiator dosage, reaction temperature, monomer concentration and emulsion polymerization technology. Compared with fluorinated polyacrylate (FP) without nano silica, FSP showed better thermal stability. The cotton fabrics treated with FSP emulsion achieved excellent water and oil repellency. The contact angle reached 154°for water and 107°for n-hexadecane.(4) Two series of polyhedral oligomeric silsesquioxane (POSS) based hybrid terpolymers P(POSS-MMA-(HFPO)3MA) and P(POSS-MMA-StRf) were synthesized via solution polymerization and characterized by NMR, FT-IR, GPC, XRD, TGA and DSC. TGA and DSC results showed that the thermal properties of these terpolymers were improved by the introduction of POSS cage. Effects of POSS content on the hydrophobicity and oleophobicity of the cotton fabrics treated with P(POSS-MMA-(HFPO)3MA) and P(POSS-MMA-StRf) were studied. Water and oil repellency of the treated cotton fabrics were improved by the polymer incorporation of POSS unit. For P(POSS-MMA-(HFPO)3MA), water and salad oil contact angle could achieve 152°and 144°, respectively, as POSS content in terpolymer is 13.4 wt.%. For P(POSS-MMA-StRf), water and salad oil contact angle could achieve 163°and 141°, respectively, as POSS content in terpolymer is 7.1 wt.%, and oil repellency rating of the treated cotton fabric was 5. The affecting mechanism of POSS content on the water and oil repellency of the treated cotton fabrics was discussed based on the results of XPS, SEM and elemental analysis. Moreover, the POSS segment in the terpolymer mitigated the burning of the coated cotton fabrics in air to some extent by formation the protective char layer, while the POSS/fluorinated polymer blend didn't reduce the flammability of the cotton fabrics. Finally, the terpolymers is potential to be endowed other functional groups from the unreacted vinyl groups in the POSS segments, and thus to be developed for various potential applications.
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