Easy-care properties of simultaneously grafted and crosslinked cotton fabrics

The concurrent grafting of acrylic acid (AA) and crosslinking of dimethyloldihydroxy-ethyleneurea (DMDHEU) with cotton fabric in the presence of ammonium persulfate [(NH4)(2)S2O8)], magnesium chloride hexahydrate (MgCl2 . 6H(2)O), and ammonium chloride (NH4Cl) catalysts were studied. These salts were separately used or as a binary mixture of (NH4)(2)S2O8/MgCl2 . 6H(2)O or (NH4)(2)S2O8/NH4Cl. The pad-dry-cure method was employed for the fabric treatment under a variety of conditions. The latter include the nature and kind of the single catalyst as well as pair-mixed catalysts, the concentrations of the catalyst and AA, and temperature and duration of curing. The effects of these conditions on the values of the carboxyl content and crease recovery angle (CRA) of the treated fabrics were evaluated. The tensile strength, elongation at break, dyeability, aqueous and nonaqueous oily soiling, and soil-release properties of the treated fabrics were also examined. Results obtained indicated that all treated fabrics have superior properties, except tensile strength and elongation at break, as compared with the untreated fabric (control). However, beside the AA-grafting and DMDHEU-crosslinking reactions, there are other types of reactions catalyzed by the salts used, viz., the addition reactions between AA molecules and the cellulosic hydroxyls as well as between AA and DMDHEU hydroxyls. The tentative mechanisms for these reactions are suggested. (C) 1996 John Wiley & Sons, Inc.