Development of Eco-Friendly Cotton Fabric Reinforced Polypropylene Composites: Mechanical, Thermal, and Morphological Properties

To determine the possibility of using cotton fabric (CF) as reinforcement in the thermoplastic polymer matrix, woven CF-reinforced polypropylene (PP) composites were fabricated by the compression molding of PP sheets with 20% and 30 wt% of CF. The fabrication process involved laying up multiple layers of woven CF between precut extruded sheets of PP and compression molding to achieve 3.5-4.0 mm CF-reinforced PP composite laminate sheets. From the laminated sheets, test specimens were prepared and tested for tensile, flexural, and impact properties. It was found that the reinforcement of PP with 30% CF increased the tensile strength from 21.87 to 28.07 MPa, tensile modulus from 618 to 1867 MPa, flexural strength from 21.7 to 45.3 MPa, and flexural modulus from 813 to 1925 MPa. However, the tensile elongation at break decreased marginally from 26.72% to 20.99%. A multiaxial impact test indicates reduction in the total energy absorbed and the peak force of the fabric-reinforced laminates in comparison with neat PP. Coefficient of thermal expansion results on CF-reinforced PP laminate sheet indicate reduction in thermal expansion. Dynamic mechanical analysis of CF-reinforced PP shows an increase in the storage modulus and loss modulus. Scanning electron microscopic images reveal fibers pull out and breakages due to lack of an interfacial interaction between the CF and the PP matrix. (C) 2012 Wiley Periodicals, Inc.