Effect of the Addition of Oil Palm Mesocarp Fibers on the Physical and Mechanical Properties of a Polyester Matrix Composite

Abstract

This work focuses on the assessment of oil palm mesocarp fibers as reinforcement in a composite material with an unsaturated polyester matrix. Several volume ratios of OPMF reinforcement (0 to 15%) were used, the fibers being distributed randomly. The resulting composite was characterized on the physical and mechanical aspects. Physically, the true and apparent densities were determined as well as the porosity rate. It appears that the addition of fibers further lightens the composite and increases the porosity. The water absorption rate of the different composites samples was evaluated. The more fibers the composite contains, the higher its water absorption rate. On the mechanical aspect, the bending modulus of elasticity, bending stress at break, and breaking strain were evaluated through a three-point bending test on all combinations. The same parameters were also evaluated for certain combinations by a unidirectional tensile test. It appears from this mechanical characterization that the volume fraction of 5% reinforcement has the highest specific modulus. Impact tests were performed on samples of this combination using several sizes of reinforcing fibers. Impact resistance is enhanced as the size of the inclusion increases. The Halpin-Tsai micromechanical model for randomly distributed short fiber composites was used for the inverse approach determination of the theoretical moduli of the matrix and OPMF, then in a direct approach to determine the elastic modulus of the composite at 7.5% reinforcement.

Effect of Raphia vinifera Fibre Size and Reinforcement Ratio on the Physical and Mechanical Properties of an Epoxy Matrix Composite: Micromechanical Modelling and Weibull Analysis

“…The porosity rate was determined in accordance with ASTM D 2734-03 [44]. The porosity rate p (%) was determined by Equation ( 4) and used by other authors for the evaluation of the porosity of palm kernel mesocarp fibre-reinforced composites [41] p…”

“…The pre-weighed samples were immersed in distilled water and then weighed until a constant mass was obtained [41].…”

“…The tensile test was carried out on an MTS 20/M tensile testing machine with a test speed of 5 mm/min and a load cell of 20 kN, the distance between jaws being 105 mm. The tensile strength and Young's modulus in tension were determined by Equations ( 6) and (7) [41,49]:…”

Extraction and characterization of a novel tropical fibre Megaphrynium macrostachyum as a biosourced reinforcement for gypsum-based biocomposites

“…It is interesting to note that these trends (Figure 8) are well predicted by this model, whatever the nature of the fibre (MMB, MMK and MMKW). The slight deviations (∼2%–6.4%) observed can probably be attributed to several factors such as (i) structural defects in the gypsum composite (air bubbles, out-of-plane orientation of the fibres), 61 (ii) porosity, water sensitivity, porosity and the large variability in fibre diameter and mechanical properties, 62 and (iii) the difference in the number of contacts at the fibre-matrix interface. 62

Figure 8.Evolution of the theoretical and experimental flexural modulus of elasticity as a function of the fibre volume fraction.

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“…The slight deviations (∼2%–6.4%) observed can probably be attributed to several factors such as (i) structural defects in the gypsum composite (air bubbles, out-of-plane orientation of the fibres), 61 (ii) porosity, water sensitivity, porosity and the large variability in fibre diameter and mechanical properties, 62 and (iii) the difference in the number of contacts at the fibre-matrix interface. 62

Figure 8.Evolution of the theoretical and experimental flexural modulus of elasticity as a function of the fibre volume fraction.

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