Bark cloth structure and properties: A naturally occurring fabric and ancestral textile craft from Uganda

Abstract

Natural fabrics from two bark trees of Uganda (“Kilundu”: Antiaris toxicaria and “Mutuba”: Ficus natalensis) are being considered today for the local footwear industry. Here, we thoroughly examined to determine their structural, biochemical and mechanical properties of the two bark cloths, in order to ascertain their potential use as locally-available, low-cost composite reinforcements and eventually for a use in textile industry as well. Fibres in both fabrics are rich in highly crystalline cellulose (76.6 ± 4.9% and 66.3 ± 0.5%) and have very cohesive cell walls with small lumen size and stiff middle lamellae. However, their low indentation modulus is due to a high microfibrillar angle, penalizing their longitudinal stiffness but making them interesting for impact or deformation performance. The two fabrics exhibit layers of preferred fibres orientations, quasi similar to unidirectional or +/-45° preforms, and hence may be used “as produced” as polymer reinforcements in technical composites but also in textile sector, in place of leather. Finally, their water uptake behaviour (21.2%-wt for Mutuba and 13.8%-wt for Kilundu) indicates opportunities for a range of environmentally-sensitive applications.