Effect of alkali treatment on physical properties of banana fibre

Banana fibres have been treated with NaOH at 10, 15 and 20% concentrations and its effect on chemical composition, and physical, morphological, structural and thermal properties are studied. The raw and alkali-treated fibres have been investigated for diameter, density, moisture regain, colour, surface characteristics, functional groups analysis, crystallinity of fibres and thermal behavior. The treated fibres show improvement in cellulose content, lignin removal, tenacity, crystallinity, and thermal resistance till 10% concentration, and after that no improvement is observed beyond 15%. Colour has turned the fibre towards darker side slightly aesthetically unappealing. It is noted that the 15% NaOH concentration is optimum for treating banana fibres used as reinforcement.