Study On Synthesis And Surface Properties Of Fluorinated Acrylate Copolymer Emulsion

Polyacrylate emulsion are classical polymers and have been studied intensively because of their excellent film-forming, thermal stability, chemical stability. Copolymerization with fluorinated acrylate greatly increased the ability of polymer scientists to tailor-make polymers with specifically desired properties. The polymers of fluorinated acrylate have many special performances such as low surface free energy, excellent hydrophobic and oleophobic performance, the chemical stability and the weather-resistant, because of unique long chain fluorinated alkyl structure introduced.The fluorinated acrylate was synthesized by hexafluoro propylene oxide through the ring opening reaction, addition reaction and esterification with HEMA. Several fluorinated acrylate latex with different fluorine content were prepared with fluorinated acrylate (FA) and butyl acrylate (BA) as monomers, ammonium persulfate (APS) as initiator, sodium dodecyl sulfate (SDS), perfluorooctanesulfonic acid potassium salt (FC-80) and fatty alcohol polyoxyethylene ether (AEO-9) as emulsifiers under various reaction conditions. FTIR and NMR were used to confirm the molecule structure. The factors of influence on kinetics of emulsion polymerization were studied in detail and conclude the reaction rate equation of the constant speed time in polymeration was Rp=Kp[M]1.07 [I]0.47[E]0.71The emulsion stability was studied by coagulation rate and Zeta potential in detail. Surface properties of the latex film were investigated by TGA, DSC, ATR-IR, XPS, contact angle respectively. The results showed that the hydrophobic and oleophobic performance increased with increasing the concentration of FA, the contact angles for latex films to water and oil were up to 125.4°and 82.7°respectively and surface free energy reached 18.45 mJ/m2. The fluorine-containing groups could migrate and enrich on the surface through ATR-IR and XPS.The blend emulsion was prepared from fluorinated acrylate emulsion and waterborne polyurethane emulsion. Its hydrophobic and oleophobic performance was investigated by contact angle. The result showed the contact angles for latex films to water and oil were up to 107.5°and 57.6°respectively with 1 wt% 30%-PFA, which greatly enhanced the hydrophobic and oleophobic performance of polyurethane.