Synthesis And Properties Of Waterborne Fluorinated Polyacrylate Emulsion With Nanoscale Core-Shell Structure

Many important properties of solid material are dependent on the surface chemical structure and elemental composition.Polymers containing perfluoroalkyl side chains have attracted much attention due to their unique properties,such as Low surface energy,high chemical and thermal stability,outstanding antiadhesive and oil-repellent properties,low refractive index and low dielectric constant,and are used widely in the textile,coatings and carpet industries.Among of them,perfluoroalkyl substituted acrylates copolymer have emerged as the most commonly used low-surface-energy polymer coatings for textiles,paper, leather and wood.Recently,because of the increasing resource and environmental awareness, it is strongly desirabe to develop waterborne fluorinated copolymer emulsion with anticipated macromolecular structure and properties,and after coating,the fluorinated groups can easily be migrated and enriched on the surface so that the amount of expensive fluorine components in the polymer is reduced considerably.The content and conclusions of this dissertation are as follows:1.By using Tetrahydrofuran as the solvent,perflurooctanoic acid was reacted with glycidyl methacrylate to yield 2-hydroxy-3-(methylacryloyloxy)propyl perfluorooctanoat. The chemical structure of product was confirmed by means of FTIR,¹³C-NMR and Mass spectroscopy methods.2.By using APS/SHS redox system as initiator,and SDS/OP-10 as commixture emulsifier,the core-shell fluorine-containing polyacrylate latexes with poly(butyl acrylate-co-isobornyl methacrylate) core and poly(butylacrylate-co-isobornyl methacrylate-co-2-hydroxy-3-(methylacryloyloxy)propyl perfluorooctanoat) shell were prepared by pre-emulsified three-stage semicontinuous emulsion polymerization.3.The stabiliy of emulsion and the effects of components dosage on the emulsion polymerization were studied.The structures of core-shell copolymers were studied by FTIR, IH-NMR,TEM,DSC,GPC and Partical Size Distribution methods.The properties of film were studied by ATR-FTIR,AFM,TGA,XPS,Water Absorption,Water and Hexadecane Contact Angle Measurement methods.The results showed that the fluorine-containing groups could migrate and enrich on the surfaces.When the fluorine content was 7.7wt%,the calculated surface energy was 15.5mJ/m²,which was lower than polytetrafluorethylene (22mJ/m²),exhibiting excellent water and oil repellency.4.The reaction of methacrylic acid with oxalyl chloride gave methacryloyl chloride at room temperature.Under the catalysis of triethyl amine,methacryloyl chloride was reacted with 2-aminoethanol for 5h at 0℃and 20h at room temperature to yield N-(2-Hydroxyethyl)methacrylamide.The acylchloridization occured between the perfluorooctacid and thionyl chloride to obtain perfluoroacyl chloride.Then, methylacryloylamidoethyl perfluorooctanoat was successfully obtained by reaction of perfluoroacyl chloride with N-(2-hydroxyethyl)methacrylamide for 46 h at room temperature. The chemical structure of product was confirmed by means of FTIR,¹³C-NMR and Mass spectroscopy methods.