Enhancement of Physical and Mechanical Attributes of a Natural Fiber-Reinforced Composite for Engineering Applications

A natural fiber based polymer composite has the advantage of being more environment-friendly from a life cycle standpoint when compared to composites reinforced with widely-used synthetic fibers. The former category of composites also poses reduced health risks during handling, formulation and usage. In the current study, jute polymer laminates are studied, with the polymeric resin being a general purpose polyester applied layer-by-layer on bi-directionally woven jute plies. Fabrication of flat laminates following the hand layup method combined with compression molding yields a jute polymer composite of higher initial stiffness and tensile strength, compared to commonly used plastics, coupled with consistency for engineering design applications. However, the weight-saving potential of a lightweight material such as the current jute-polyester composite can be further enhanced through improvement of its behavior under mechanical loading. A weakness of a natural fiber reinforced composite is its propensity for moisture absorption which can lead to a substantial degradation in its stiffness and strength. In the current study, it is shown that addition of a limited number of plies of a lightweight metal such as an aluminum alloy in a meshed state can lead to substantive improvement in its physical and mechanical properties such as a 7.4% drop in mass for same surface area, a 57% increase in tensile modulus and a 12% rise in tensile strength. A noticeable enhancement in hygroscopic response of the hybrid jute composite has also been found in the moisture-absorption study that was carried out. It is noted that the hybrid jute-aluminum laminate investigated here has not been reported earlier in published literature. The current strategy of hybridization can be potentially extended to a wider class of natural fiber reinforced polymeric composites.