Vapor-Phase Deposition of Surface Polymers and Cross-Linking on Cotton Fabrics

Vapor-phase deposition of selected polymers on cotton fibers offers certain potentially attractive characteristics over conventional liquid-phase textile processing. These include uniformity and completeness of coverage at low add-on's in the absence of solvents, lower reaction temperatures and/or shorter exposure times, and use of reactants normally sensitive to water and solvents, all or some of which may result in a more favorable balance of the performance properties of such polymer-coated cottons. High molecular-weight polyoxymethylene polymer deposits were obtained by the immersion of cotton fabrics in a suitable alkaline catayst solution at ambient temperatures and in air, followed by exposure of the catalyzed cloths to purified monomeric formaldehyde vapor. Polyamide polymer deposits were realized by modified interfacial polymerization tech niques, also under mild reaction conditions. The properties of these polymer-coated cotton fabrics were determined over a range of polymer add-on's, with emphasis on the effects of treatments with various cross-linking agents. Both methylo lamide-treated, polyoxymethylene-coated and diisocyanate-treated polyamide-coated cotton fabrics were found to exhibit significant improvements in wrinkle recovery and other performance properties with superior strength retention at relatively low polymer add-on's, compared to conventionally cross-linked fabrics.