Development of moisture vapour permeable waterproof cotton fabric by coating with blend of natural rubber latex and polyvinyl alcohol
Journal of the Textile Institute
Cotton fabric was coated with aqueous dispersion containing blend of natural rubber latex (NRL), polyvinyl alcohol (PVA) and starch following a knife-over-roll technique to produce moisture vapour permeable waterproof coating. Coating of cotton with a formulation containing NRL, 15% aqueous PVA and tamarind kernel seed powder as starch, in the ratio of 1:3: 0.3 in presence of a typical sulphur curing system, followed by drying of the coated fabric at 95 °C for 5 min and subsequent vulcanization at 120 °C for 2 h produced most balanced improvements in the properties of the coated fabric such as, waterproofness, breathability as revealed by moisture vapour transmission rate, coating adhesion, tensile properties, abrasion resistance and flex endurance. Incorporation of PVA makes the coating permeable to moisture vapour and such property is promoted further in presence of starch in the coating formulation. Examination of surface morphology of vulcanized coating by scanning electron microscopy revealed that poly vinyl alcohol crystals formed clusters of dimensions of only few microns in the rubber matrix. Such clusters of PVA served as conduits for transportation of moisture vapour through the film of NRL while acting as an effective barrier to liquid water droplets.
Link to Published Version
Das, D., Chaudhuri, A., Mitra, M., & Ghosh, S. (2017). Development of moisture vapour permeable waterproof cotton fabric by coating with blend of natural rubber latex and polyvinyl alcohol. The Journal of The Textile Institute, 108(8), 1285–1290. https://doi.org/10.1080/00405000.2016.1242461