Tensile Properties of Polycarbonate Coated Natural Fabric Sterculia Urens: Effect of Coupling Agent.

The natural fabric from the tree Sterculia urens was found to be composed of ligno-cellulosic fibres arranged in a rarely occurring uniaxial direction. In order to assess the suitability of Sterculia fabric as reinforcement and polycarbonate as matrix, this uniaxial fabric was coated with polycarbonate. The tensile properties of both uncoated and polycarbonate coated fabrics were studied. The tensile parameters such as maximum stress, Young s modulus, and elongation-at-break were determined using the Universal Testing Machine. The effect of alkali treatment, coupling agent and the polycarbonate coating on tensile properties was studied. The morphology of the fabric before and after alkali treatment and polycarbonate coating was studied using the scanning electron microscopy and polarized optical microgram techniques, respectively. The improved tensile properties of polycarbonate coating was attributed to the filling up of void regions of uniaxial fabrics with polycarbonate facilitating continuity and also better interfacial bonding between the fabric and polycarbonate. The effect of the coupling agent on the structural changes, morphology and the tensile properties of the neat and alkali treated Sterculia fabric was also studied. Marked changes on the surface of the fabrics were noticed when the coupling agent was used.