Characterisation of Natural Fibres for Sustainable Discontinuous Fibre Composite Materials

Abstract

Growing environmental concerns and stringent waste-flow regulations make the development of sustainable composites a current industrial necessity. Natural fibre reinforcements are derived from renewable resources and are both cheap and biodegradable. When they are produced using eco-friendly, low hazard processes, then they can be considered as a sustainable source of fibrous reinforcement. Furthermore, their specific mechanical properties are comparable to commonly used, non-environmentally friendly glass-fibres. In this study, four types of abundant natural fibres (jute, kenaf, curaua, and flax) are investigated as naturally-derived constituents for high performance composites. Physical, thermal, and mechanical properties of the natural fibres are examined to evaluate their suitability as discontinuous reinforcements whilst also generating a database for material selection. Single fibre tensile and microbond tests were performed to obtain stiffness, strength, elongation, and interfacial shear strength of the fibres with an epoxy resin. Moreover, the critical fibre lengths of the natural fibres, which are important for defining the mechanical performances of discontinuous and short fibre composites, were calculated for the purpose of possible processing of highly aligned discontinuous fibres. This study is informative regarding the selection of the type and length of natural fibres for the subsequent production of discontinuous fibre composites.

Tucum Fiber from Amazon Astrocaryum vulgare Palm Tree: Novel Reinforcement for Polymer Composites

“…Previous works reported L c for natural fibers such as coir (12.4 mm), PALF (7.3 mm), kenaf (5.37 mm), flax (2.22 mm), jute (0.84 mm) and curaua (0.79 mm) in epoxy matrix. For the interfacial strength the values found for these same natural fibers were: coir (1.42 MPa), PALF (4.93 MPa), kenaf (6.41 MPa), flax (11.83 MPa), jute (11.64 MPa) and curaua (12.93 MPa) [ 49 , 50 , 51 , 52 ]. One can observe in Equation (3) that the L c is inversely proportional to the interfacial strength.…”

Mechanical Properties of Natural Fiber Reinforced Foamed Concrete

“…The interest in materials reinforced with natural fibers is growing because it is possible to obtain materials with good mechanical properties, low density and low cost. In addition, natural fibers are biodegradable, renewable and promote sustainability [ 12 , 13 , 14 , 15 ], which is increasingly important currently. These fibers could replace synthetic fibers in certain applications, since synthetic fibers leave a greater environmental footprint.…”

A Life Cycle Engineering Perspective on Biocomposites as a Solution for a Sustainable Recovery

“…As a rule of thumb, unless a natural fibre has undergone additional processing, it has a rougher surface compared to a synthetic fibre. In principle, this can aid mechanical interlocking with the matrix, but the presence of hydrophilic hydroxyl groups may form hydrogen bonds with adventitious moisture, competing with those formed with a polar matrix resulting in poor mechanical performance as a composite [82]. Additionally, the reactive functional groups of the natural fibre may be covered by pectin and waxy substances that behave as a barrier, preventing effective fibre-matrix bonding [123].…”