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Natural fibers are exceptional renewable resources to develop biocomposite materials for reducing the negative effects on the environment and producing economical and lightweight materials for load bearing semi‐structural applications. The present study is an attempt to develop kenaf/pineapple reinforced bio‐epoxy biocomposite and investigates thermo‐mechanical and viscoelastic properties under accelerated weathering conditions. The compression molding technique is used to develop biocomposite with four different arrangements of kenaf/pineapple laminates. To perform accelerated weathering, laminates are exposed to ultraviolet radiation and humidity conditions with extreme temperature in weathering tester machine. The tensile, flexural, impact, thermogravimetric analysis, thermal conductivity, viscoelastic properties, and water absorption tests are performed before and after accelerated weathering. The results revealed that the hybridization of kenaf/pineapple laminates showed better interfacial strength and stiffness while reducing the moisture sensitivity under accelerated weathering conditions. The morphology and fracture behavior of biocomposites are examined with scanning electron microscopy.

Introduction In fractures, electrical properties are generated by the piezoelectric effect and cellular activity, initiate and augment healing. Monitoring these can result in the development a diagnostic tool for diagnosing delayed and early non-union of bones and may enable the clinician to change the line of treatment for decreasing the suffering time of the patient. This article summarizes 12 studies related to the electrical properties of bones for the monitoring of fracture healing. Materials and methods This experience has been used to develop a methodology comprising insulated fixators and measurement of electrical properties by an LCR (inductance, resistance and capacitance) meter at King George's Medical University (KGMU). Inductance, conductance and impedance of the fractured and normal segments of fractured human tibia were monitored. Results Prospective data analysis was performed; this showed large variances. The patients were then stratified into two groups: (i) delayed union and (ii) normal union in a blinded manner. Analysis of data ensuring blinding was done separately. Conclusion Electrical properties are highly dependent on bone mineral density, temperature, structure and cross-sectional area of the bone. Skin and soft tissue are responsible for masking the electrical signals from bones measured in vivo. Therefore, at KGMU, insulated fixators were designed to prevent short circuit by rods and enable measurement from nothing else but the bone. Electrical properties of bones, can be used as a biomarker for monitoring fracture healing.

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The present study aims to investigate the effects of stacking sequence on physical, mechanical and moisture resistant properties of pineapple leaf fiber (PF) and flax fiber (FF) reinforced composite laminates. The non-hybrid and hybrid composite laminates are fabricated by using vacuum assisted resin infusion molding process (VARIM) with an inter-ply configuration. From the results, the maximum tensile strength (219.3 MPa), flexural strength (132.4 MPa), shear strength (39.1 MPa) and impact energy (50.2 J) have been recorded for FFRP composites while the minimum for PFRP (124.7 MPa, 52.3 MPa, 4.3 MPa, and 23.3 J) respectively. For hybrid composite laminates, the increase in volume fraction of flax fiber, improved the mechanical and moisture resistant properties while an increase in the volume fraction of PALF enhanced the elongation and flexibility of the developed composites. Furthermore, it observed that, stacking sequence configuration of flax fibers as outer layer exhibited better tensile, flexural, impact and moisture properties while flax fibers at inner layer examined maximum shear properties. Therefore, among hybrid composites, H7 recorded maximum tensile strength, flexural strength and impact energy (207.7 MPa, 121.7 MPa and 48.8 J) while H5 recorded maximum shear strength (24.2 MPa). The water absorption and chemical resistant behaviour of fabricated laminates with five different combinations of solution (distilled water, seawater, hydrochloric acid, sulphuric acid and sodium carbonate) are examined and revealed that hybrid composite laminates have better resistance to water and chemical uptake. The morphology and fracture analysis of composite laminates are analyzed with scanning electron microscopy (SEM). Overall, the developed hybrid composite laminates have lighter weight, economical and better interfacial bonding with improved mechanical and moisture properties for distinct load-bearing applications.

The present study is focused on investigating the effect of the micro-mechanical properties of the natural fiber- (pineapple leaf fiber) reinforced polymeric composites by the addition of pineapple leaf micro-particulates. For the investigation, a two-step approach has been used. In the first step, finite element method-based analysis has been used to characterize the tensile and shear properties of the pineapple leaf fiber-reinforced polymeric composites (FRP) and pineapple paticulate-reinforced polymeric composites (PRC), and the adopted finite element method-based analysis has been validated through the experimental approach. In the second step, the validated finite element method-based analysis has been used to characterize the micro-mechanical properties of the hybrid fiber-reinforced polymeric composites (HFRP) fabricated using the pineapple leaf micro-particle embedded epoxy as a matrix material and the pineapple leaf fiber has been used as reinforcing material. It has been observed through the analysis that the micro-mechanical properties of HFRP were superior to that of FRP. There has been a 10.16% increment in Young’s modulus in the longitudinal direction and a 26.36% increment in Young’s modulus in the transverse direction for HFRP over FRP. Further, a 9.91% increment for in-plane shear modulus and 26.17% increment in outer-plane shear modulus have been observed for HFRP in comparison to FRP. These results suggest that pineapple leaf particulates are good reinforcing materials to enhance the transverse direction and outer plane micro-mechanical properties of the fiber-reinforced composite.