Mechanical properties and water sorption behavior of phenol-formaldehyde hybrid composites reinforced with banana fiber and glass fiber

Banana fiber, which is rich in cellulose, relatively inexpensive, and abundantly available, has potential for polymer reinforcement. This study explores the merits of combining high-modulus glass fibers with banana fiber in phenolic resoles to develop high-performance, cost-effective, lightweight hybrid composites. Of particular interest is the effect of varying layering patterns of banana fiber and glass fiber on the tensile, flexural, and impact properties of hybrid composites. The highest tensile strength value has been obtained for an intimate mixture of both fibers, and the maximum flexural and impact strength has been obtained for composite samples prepared from interleaving layers of banana fiber and glass fiber. Tensile, flexural, and impact properties of the composites increase with an increasing volume fraction of glass fiber. The water uptake of these composites decreases with the incorporation of glass fiber into banana fiber, and the composites with glass fiber at the periphery and banana fiber at the core have the maximum resistance to water absorption. Scanning electron micrographs show the fracture mechanism and fiber/matrix adhesion in these composites (C) 2008 Wiley Periodicals, Inc.