A Study of Tearing in Coated Cotton Fabrics 1

The influence of fabric construction on the mechanial prop erties of polyvinyl chloride coated fabrics was discussed in previous work.⁴ Eight of the fabrics used in this work were selected for further study. Six PVC plastisols were used, including the one used previously, and the same formulation modified to obtain different viscosities and moduli. In addition, two pretreatments were used. Five of these fabrics were also coated with polyvinyl butyral in a solvent system, and polyurethane in both a solvent system and as a latex.

Measurements of tensile properties, tearing strength, and flexural rigidity were made for all coated samples. These samples permitted an examination of the influence of changes in coating viscosity, modulus, penetration, and chemical type on these properties. The results showed that the mechanical properties of a coated fabric are affected primarily by the coating which penetrates the fabric structure. This effect is related to the mechanical inter action of coating and fabric, and there is no reason to suppose that it would be related in any important way to the chemical nature of the coating. All of this work has suggested that high tearing strengths can be achieved with any type of coating, provided the shape of the coating-fabric interface, as well as the deformability of the coating which penetrates the major fabric pores, can be appropriately controlled.