ABSTRACT
The desire for environment-friendly materials and sustainability has brought a paradigm shift in the way engineers and the entire material research community thinks while attempting to develop new material, particularly for engineering applications. This study is carried out to underscore the suitability of particulate moringa oleifera fruit pod (MOFP) reinforced epoxy bio-composites on selected properties for structural applications. The dried waste fruit pods were processed as calcined and pulverized fruit pod particulates, respectively. Their respective bio-composites were developed by blending the selected materials in predetermined proportions using the open mould processing method. The MOFP particles were characterized with SEM/EDS and XRD while mechanical and wear properties of the developed bio-composites were evaluated. The results showed that the pulverized MOFP reinforced epoxy bio-composites showed improved properties than the calcined MOFP bio-composites in most of the properties considered. This was noticed to be due to the presence of more elemental constituents and at higher proportions in pulverized particles than in the calcined particles. It was discovered that 15 wt.% pulverized MOFP reinforced epoxy bio-composites gave about 67.9%, 28.7%, 8.8%, and 8.8% enhancement and with a value of 70.2 HS, 39.02 MPa, 198.4 MPa, and 753.28 MPa in hardness, flexural strength, flexural modulus, and tensile modulus, respectively to emerge as the reinforcement content with the optima properties. Based on the findings, MOFP particles reinforced epoxy-based biocomposites can be used in applications where stiffness and high strength are not essential requirements; packaging applications; in electrical component applications such as circuit boards, and cables due to their low thermal conductivity.
ABSTRACT
In this research, hydroxyapatite (HAp) was synthesized from chicken eggshell waste by hydrothermal method for the development of bio-composite material suitable for biomedical implant. However, since environmental influences on natural materials are unique for different geographical locations in the world, the use of agro wastes from these locations need to be investigated. This work provides the detail results of the potentials of eggshell as HAp source. High-density polyethylene (HDPE)/HAp composites were developed by random dispersion of Hap (10, 20, 30 and 40 wt.%) in HDPE matrix, and were designated as HAC10, HAC20, HAC30, and HAC40. The HAp-filled HDPE composites were developed by a hot compression moulding process. The samples were subjected to tensile, flexural, impact, fracture toughness and wear tests according to ASTM standards in order to establish their structural performance as an implant material. Furthermore, the samples were also tested for hydrophilicity using tap water and simulated body fluid (SBF). X-ray diffraction analysis showed strong peaks of hydroxyapatite phase which established that the influence of the selected processing conditions on the poultry eggshell as a natural source for the biomedical application was suitable for the synthesis of high-quality hydroxyapatite. The mechanical properties of the developed composites were enhanced to the level of the required properties expected of an implant material compared to the control sample except for impact strength. Water absorption characteristics of the developed composite samples also displayed expected behaviour in SBF solution than in tap water thereby promoting the material as a good implant material. From the results, the sample with 40 wt.% HAp possess the highest values in the mechanical properties examined while sample from 20 wt.% had the best fracture toughness. The results revealed that these waste eggshells could be successfully converted into useful biocompatible HAp particles needed for the enhancement of the mechanical properties of polymer composites to meet the structural challenges of bio-composites.
ABSTRACT
This work was carried out to investigate the influence of cow bone particle size distribution on the mechanical properties of polyester matrix composites in order to consider the suitability of the materials as biomaterials. Cow bone was procured from an abattoir, washed with water, and sun-dried for 4 weeks after which it was crushed with a sledge hammer and was further pulverized with laboratory ball mill. Sieve size analysis was carried out on the pulverized bone where it was sieved into three different sizes of 75, 106, and 300 µm sieve sizes. Composite materials were developed by casting them into tensile and flexural tests moulds using predetermined proportions of 2, 4, 6, and 8%. The samples after curing were striped from the moulds and were allowed to be further cured at room temperature for 3 weeks before tensile and flexural tests were performed on them. Both tensile and flexural strength were highly enhanced by 8 wt% from 75 µm while toughness was highly enhanced by 6 and 8 wt% from 300 µm. This shows that fine particles lead to improved strength while coarse particles lead to improved toughness. The results show that these materials are structurally compatible and are being developed from animal fibre based particle; it is expected to also aid the compatibility with the surface conditions as biomaterials.
