PREPARATION AND CHARACTERIZATION OF PLANTAIN FIBRES REINFORCED POLYMER COMPOSITE

Abstract

The research herein presented, focuses on the extraction of natural fibre from plantain (Musa paradisiaca) pseudostem its modification and application for the production of reinforced polymer composite. Plantain fibres were extracted from 3-year-old stem using water ratting methods with a time interval of 7days for 35 days. Physical and chemical treatments such as Alkali (NaOH), permanganate (KMnO4) and Microwave treatments were conducted on the plantain fiber. Alkali treatment of the fiber was carried out using 1-5% NaOH for a duration of 1-4hrs. For KMnO4 treatment, the extracted fibres were soaked in 0.01%, 0.05% and 0.1% KMnO4 –acetone solution for 1-3mins. Physical modification of the fiber was done by using high-frequency microwave irradiation under different conditions in terms of power and time. Density of the fibres was determined as per ASTM D3800-99. Plantain fiber reinforced epoxy composites were fabricated for different fiber volume percentage (5, 10, 15 and 20%) by hand layup technique. The composite having 15% fiber volume fraction was found to have better mechanical strength in comparison to others. Hence, 15% volume fraction of the fiber was kept constant for the fabrication of all composites in the entire study. In order to identify the effect of these modifications on the macromolecular, morphological, crystallographic structures, thermal properties and mechanical properties of the fibers and the reinforced polymer composite, X-Ray Diffractometer (XRD), Fourier Transform Infra-red spectrophotometer, Thermogravimetric analyzer (TGA), Scanning Electron Microscope (SEM) and Instron testing machine were used. For Alkali and KMnO4 treatments, X-Ray Diffraction analysis ix shows significant changes in the macromolecular and the crystallographic parameters of the fiber, Fourier Transform Infra-red (FTIR) spectra confirm the partial removal of wax, hemicellulose, and lignin content. Thermogravimetric analysis (TGA) shows that thermal stability of the fibres increase after treatment. Mechanical test results revealed improved strength of both fiber bundle and reinforced composite after treatment. Scanning Electron Microscope (SEM) images indicate enhance surface roughness of treated fibres. Microwave radiation at 550W power was able to improve the mechanical properties of the fibre with increase surface roughness. However, at 750W power of microwave irradiation, a decrease in the mechanical properties of the fibre and fibre reinforced composite was observed. A serious damaging effect on the surface of the fibre, due to degradation and rupturing of fibre cells was revealed. Improved mechanical strength was observed for fibre reinforced composites after treatments.