Synthesis And Properties Of Three Kinds Of Cross-Linking Modified Fluorinated Acrylate Emulsion Polymerization

Currently, the fluorinated acrylic polymer have been widely used in the fields of coatings, spinning and leather because of its excellent weather resistance, corrosion resistance, water resistance and solvent resistance. However, since the structure of uncross-linked fluorinated polymers are a linear molecular structure, the gloss, water resistance and solvent resistance of latex film are poor, the hardness, tensile strength and other mechanical properties are relatively less. Therefore, in the lecure study three kinds of cross-linked system of crosslinked acrylate modified fluorinated acrylic polymer.The core-shell laexes containing epoxy groups in the shell layer were synthesized by copolymerization of glycidyl methacrylate(GMA), IBOMA and n-butyl acrylate(BA) uses seeded semicontinuous emulsion polymerization. The core-shell latexes containing carboxyl groups on the shell layer were synthesized by seeded semicontinuous emulsion of AA with BA and IBOMA. The reactive blend latexes were obtained by blending epoxy group functional latex and carboxyl group functional latex. The core-shell morphology of latex particles was clearly obserbed by TEM. The size and distribution of the latex particles were measured by DLS analysis. The latex particles exhibited narrowdispersed with polydispersity of 0.002 and number-average diamter of 108nm. The effect of cross-linked polymer network density on was solvent properties and water resistance were investigated by measurement of gel content ratio and water absorption. The results show that the denser crosslinked network, the more difficult water molecules and solvent molecules to enter in. The influence of different fluorine monomer and crosslink density of latex film surface properties were studied by measurement of water contact angle. The results indicated that the content of fluorine monomer increases, the hydrophobic oleophobic properties increased; and the density of cross-linking increases, the fluorocarbon chain in the membrane will be more stable, the film surface will be more stable.NMA modified fluorine containing acrylic elmusion with core-shell structure was synthesized by seeded semi-continuous emulsion polymerization of NMA, AA as crosslinking monomers. The results show that when the amount of NMA is 4%, the emlution gel conten raio is 0.39%, and the emlsion has good ion stability and storage stability. The core-shell morphology of latex particles was clearly obserbed by TEM. The size and distribution of the latex particles were measured by DLS analysis. The thermal stability of polymer was measurement by TGA. The result indicated that conpared with uncrosslinking fluorine containing acrylic polymer, the water absorption of NMA modified acrylic polymer film decreased from 6.3% to 3.9%, the gel content increaced from 90% to 95%, whinch showed that the water resistance and solvent resistance of the polymer have been greatly improved.Add Zn2+ into the prepared core-shell acrylate emulsion and synthesizedthe zinc acrylate copolymer, and studied the influence of Zn2+ density on the film. It has found out that the founctional monomer -COOH could crosslink with Zn2+, and it could produce the founactional regiment with the character of antifouling. Along with the increasing of the density of Zn2+, the film's regular function has been affected, the water resistance and solvent resistance of the polymer have been greatly improved.