SYNTHESIS OF FLUORINE-CONTAINING DISPERSIONS AND AN ENVIRONMENTAL SCANNING ELECTRON-MICROSCOPE ANALYSIS OF THEIR MORPHOLOGY WHEN APPLIED TOCOTTON FABRICS

Environmental scanning electron microscopy (ESEM) was used to monitor surface wetting, adsorption, and film formation of aqueous fluorine-co ntaining polymer dispersions on cotton fabrics. Performance of such di spersions, useful as water, oil, and soil repellent finishes, was corr elated with homopolymer and copolymer composition. In addition to the commercially available fluorine-containing dispersions (Dipolit(R) 480 ), model dispersions of hydrophobic and amphiphilic fluorine-containin g polymers were prepared. Amphiphilic copolymer dispersions were obtai ned by emulsion copolymerizations of perfluorooctylethylmethacrylate w ith hydrophobic trimethylsilylmethacrylate, which serves as a precurso r of the hydrophilic methacrylic acid and permits random incorporation of methacrylic acid upon in-situ hydrolysis of lethylmethacrylate-co- trimethylsilylmethacrylate). While poly(perfluorooctylethylmethacrylat e) failed to wet cotton surfaces, incorporation of methacrylic acid pr omoted both wetting and film formation, as evidenced by film bridges b etween single fibers.