| The fluorinated polyacrylate has the extremely low surface energy because of unique long chain fluorinated alkyl structure, and it endows the substrate with good water and solvent resistance. In recent years, fluorinated polyacrylate emulsion with water as medium which is environmental friendly has attracted the increasing attention of many investigators. Fluorinated polyacrylate has a wide range of applications in surface coatings, such as water and oil repellency for textile, paper and leather. However, the relatively high market price of the fluorinated monomers restricts their practical applications. The challenge is how to minimize the amount of fluorinated compositions whereas the reasonable surface properties can be maintained. In this work, the fluorine-containing polyacrylate emulsion was prepared by core-shell emulsion polymerization, emulsifier-free emulsion polymerization and latex blending method. The preparation and characterization of the emulsion were studied, and the structure and properties of latex film were investigated. The main research contents and achievements are listed as following:Firstly, the fluorine-containing acrylate copolymer emulsion was synthesized by emulsion polymerization through semi-continuous method using DNS-628 as emulsifier, acrylic acid (AA) as functional monomer and dodecafluoroheptyl methacrylate (DFHMA) as fluorinated acrylate monomer. The effects of initiator amount, emulsifier amount, AA amount, DFHMA amount on the emulsion polymerization and properties of the latex film were studied. The latices and its films were characterized by using TG, TEM, FTIR, XPS and laser particle diameter analyzer. It is found that the latex film using DFHMA as fluorinated monomer has better surface properties, the water contact angle and cetane contact angle of the film is 105.5°and 75°respectively, while the water absorption is 12.7% and the surface energy of the film is 12.95mN/m simultaneously. The optimal polymerization condition is 0.6wt% KPS, 3.5wt% DNS-628, 1wt% AA and 8wt% DFHMA in this system, and XPS shows there is an enrichment of fluorine element on the film-air interface.Secondly, the soap-free fluorine-containing acrylate latices with core-shell structure were prepared by the pre-emulsification and semi-continuous polymerization method, using perfluorooctylethyl methacrylate (PFEA) as fluorinated acrylate monomer and monophosphoric acid allyloxy nonylphenoxy poly(ethyleneoxy)(10) ether (ANPEO10-P1) as reactive emulsifier. The effects of polymerization conditions on the conversion and polymerization stability were discussed in detail. The optimal polymerization condition is 70℃of polymerization temperature, 0.35wt% KPS, 5wt% ANPEO10-P1 , 6wt% PFEA and 3h of dropping time in this system, the average particle size of the latex is 70nm and the polydispersity is 1.02, and the water contact angle and cetane contact angle of the film is 109.5°and 82°respectively, while the water absorption is 8.8%. With the increasing of PFEA amount, the latex film shows higher water contact angle, better water-resistance and thermal stability. XPS analysis with different take-off angels proves that the fluorine concentration in the film has the tendency to extend into the film-air interface and occupy the air–film interface during the formation of the latex film. Compared to the latex film without core-shell structure, the latex film with core-shell structure shows higher fluorine concentration, which proves the core-shell structure benefit the enrichment of fluorine component at the film-air interface.Thirdly, the fluorine-containing acrylate latex with a core-shell structure was synthesized using perfluorooctylethyl methacrylate(PFEA) as fluorinated acrylate monomer and diacetone acrylamide(DAAM) as functional monomer by pre-emulsification and semi-continuous polymerization method. The ambient self-crosslinkable latex was attained with the addition of adipic dihydrazide(ADH) as crosslinking agent. The influence of DAAM and PFEA amount on the emulsion polymerization and film properties were studied. The latices and latices films were characterized by using TG, TEM, SEM, FTIR, XPS and laser particle diameter analyzer. The results show with the increasing of DAAM amount, the latex average particle size decreases, the crosslinking degree of the film increases, the water absorption of the film decrease and the thermal stability of the film increases. Compared to the addition of DAAM in core polymerization, the addition of DAAM in shell polymerization improves the crosslinking degree and the water-resistance of the latex film. Finally, the XPS analysis proves the enrichment of perfluoroalkyl groups on film-air interface.Finally, the soap-free latex of poly(trifluoroethyl methacrylate) was synthesized with ANPEO10-P1 as reactive emulsifier and phosphoric acid bis(tridecafluorooctyl) ester ammonium salt(FSP) as co-emulsifier. And by blending of poly(trifluoroethyl methacrylate) emulsion with polyacrylate copolymer emulsion, the fluorine-containing latex blends were prepared. The polymerization conditions of poly(trifluoroethyl methacrylate) latex and the influence of mass ratio of PTFEMA latex to PBA-MMA latex on the properties of latex blends were studied. The latex and latex blends were characterized by using TG, DSC, TEM, FTIR, XPS and laser particle diameter analyzer. The optimal polymerization condition of PTFEMA latex is 75℃of polymerization temperature, 12min of ultrasonic processing time, 0.6wt% KPS, 4wt% ANPEO10-P1 , and 0.4wt% FSP. With the increasing of PTFEMA mass ratio, the surface energy of the latex blend film decreases. When the mass ratio of PTFEMA to PBA-MMA is 4:5, the water contact angle and cetane contact angle is 94°and 64°respectively, showing good water-resistance and oil-resistance. XPS analysis indicates the fluorine content is 7.9% at the film-air interface and 0.9% at film-glass interface, which prove that the PTFEMA polymer has the tendency to transfer to the surface of the latex blend film during the film formation and the fluorine content enrich at the outer space of latex film.
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