Mechanical Tensile Behaviour of Tropical Waste Fibres

The mechanical characterization of natural fiber waste poses problems concerning the preparation of the fibers and their isolation to characterize them. Fibers are available in various forms: in the form of bunches (oil palm fibers), shells (coconuts), dried blocks (banana spines), entangled crushed fibers (sugar cane), etc. Isolating a fiber or bundle of fibers requires a procedure for the preparation of fiber waste which involves cutting the fibers to length. This cutting can be manual in the laboratory but must be mechanized from an industrial point of view. But the mechanically lengthened fibers are either crushed or cut, which changes their structure and affects their mechanical properties. Once insulated, the fibers can be subjected to mechanical tests such as the tensile test, which is a reference test in studies of fiber-reinforced materials. A procedure for this direct tensile test is used. The analysis of the results requires knowledge of the fiber geometry, especially the cross-section. This cross-section can be defined by direct measurement or by image processing. Both methods were applied to a set of tropical fiber wastes of Mexican origin, i.e., oil palm, sugar cane, coconut, and banana rachis fibers. These fibers were subjected to a tensile test to determine their mechanical characteristics (ultimate strength, rate of deformation at failure) and behavior. All the data acquired on these fibers are analyzed, discussed, and compared with those in the literature. This is followed by a description of their behavior and a proposal for modeling from a rheological point of view.