Mechanical Properties of Composites Reinforced by Cotton Knitted Fabric

This paper presents analytical and experimental procedures for estimating the elastic properties of plain-weft-knitted-fabric-reinforced polymer- composite material. The composite material under study is assumed to have mainly reinforcement-fiber yarns and polymer matrix. Cotton yarn and fabrics are being considered as an environmentally friendly alternative to synthetic reinforcement in polymer composites. In present investigation cotton yarn of different length were tested by tension in order to obtain the stress-strain dependence. Also cotton knitted fabric specimens of different knitting directions were tested by tension in order to obtain the stress-strain response. Elastic moduli of cotton yarn and knitted fabrics having different load span and knitting direction were obtained. Cotton knitted fabric composites with thermoset polymer matrices were manufactured and tested by tension for stiffness and strength determination. Analytically predicted using effective modulus method composite material elastic properties were compared with experimentally obtained. Key words: Cotton yarn, cotton knitted fabric, method of effective modulus