Innovated Banana Fiber Nonwoven Reinforced Polymer Composites: Effects of Pre- and Post-treatments on Physical and Mechanical Properties

Abstract Four types of nonwovens were prepared from different sections of the banana tree e.g., outer bark (OB), middle bark (MB), inner bark (IB) and midrib of leaf (MR) by wet laid web formation. They were reinforced on two different types of matrices e.g., epoxy (E) and polyester (P) to make eight variants of composites. Different concentration (5–15%) of NaOH and water repellent (WR); and different doses (100-500krd) of gamma radiation were applied in different stages of process. The properties like water absorbency, tensile strength (TS), flexural strength (FS) and elongation at break (Eb%) were investigated. OB composites were exhibited higher water absorbency, TS and FS but lower Eb% than other types of composites. Epoxy composites were found to have 16% lower water absorbency, 41.2% higher TS and 39.1% higher FS than polyester composites on an average. Alkali treatment reduced the water absorbency by 32%; improved the TS by 71%; improved the FS by 87% on an average at 15% NaOH. Water repellent treatment (on alkali treated composites) decreased the absorbency by 63% at 10% WR but increased 6.3% at 15% WR. Gamma radiation improved the TS of 30% and FS of 35% on an average at a dose of 100krd for IB and 200krd for other composites. Further increment of dose reduced both the FS and TS.