Optimization of Mechanical Properties of a Banana/Recycled PET Fibre Composite

Sustainability and environmental awareness have resulted in natural fibres gaining significant traction in the past few years in composite manufacture. Natural fibres are relatively inexpensive and biodegradable, which makes their disposal easier. There has been high pollution of single-use polyethylene terephthalate plastic bottles. The study’s main objective is to optimize the mechanical properties of recycled polyethylene terephthalate and banana fibre hybrid composite. Banana fibres were extracted using a combination of water retting and mechanical decortication. Thereafter, the extracted banana fibres were treated with sodium hydroxide solution and then characterized. During characterization, it was found that banana fibres had a moisture content of 10%, a fibre diameter of 166 μm and an average tensile strength of 58 MPa. Using hand layup, a hybrid composite with the banana fibres and the recycled polyethylene terephthalate fibres was used fabricated the hybrid composite with polyester as the resin. The mass fraction of the banana fibre was increased from 0-10%, and that of recycled polyethylene terephthalate was increased from 0-15%. The hybrid composite was fabricated using the hand layup method. The density of the composite ranged from 480 to 1025 kgm-3, and the tensile strength ranged between 9.01 to 20 MPa, compression strength from 41.7 MPa to 152.8 MPa and flexural strength from 5.6 MPa to 48 MPa. Numerical modelling of the composite properties was done using Minitab software to obtain the optimum mechanical strength properties. Additional tests like flammability and hardness tests can be carried out as a recommendation for further study. Furthermore, characterization using artificial neural networks can be done to improve the prediction of the mechanical properties of the composite.