This research presents the behavior of dombeya buettneri fiber/graphite hybrid composites which was studied to harness a favorable balance between the inherent advantages and disadvantages of natural and synthetic reinforcements. The fibers after extraction were chemically treated for surface modification. The composite was developed using compression molding process by randomly dispersing the reinforcements in the polypropylene matrix in predetermined proportions. The developed samples were tested to ascertain the response of the materials to the selected properties. Experimental results showed that hybrid composite sample C which is a blend of 12 wt% dombeya buettneri fiber (DBF) and 8 wt% graphite particle (GP) gave enhanced results in many of the properties which includes; hardness, impact, thermal insulation and abrasion resistance properties. Also, the hybrid composites sample denoted as sample E which is the blend of 6 wt% DBF and 14 wt% GP produce higher enhancement in the flexural properties and Young’s Modulus of Elasticity than other samples. Composite sample reinforced with dombeya buettneri fiber as single reinforced composites performed more in ultimate tensile strength compared to other samples while graphite particle reinforced sample emerges as the best in thermal conductivity. Diffusion of water into the composites also obeys Fick’s law where sample C was seen to be the best among the composites. It was therefore, discovered that the synergy between the two reinforcements has encouraged the improvement of polypropylene (PP) properties in a unique mode.

This study investigates the effects of calcined and uncalcined eggshell particles (ESP) and sisal fiber (SF) on the mechanical and wear properties of eggshell particles/sisal fiber reinforced epoxy composites. Egg shell was processed to obtain calcined and uncalcined egg shell particulate of −43 μm and sisal fibers was extracted by soil retting and treated with NaOH. The composite was developed using the hand lay-up method by blending the selected materials in predetermined proportions. SEM/EDS and XRD of the egg shell particles were carried out while mechanical and wear properties of the developed composites were evaluated. SEM images of the fracture surfaces were also examined. The results showed that eggshell particles contain CaCO 3 and the uncalcined ESP/SF reinforced epoxy composite showed improved properties than the calcined ESP/SF composites in most of the tests performed. Also, it was observed that most of the tests gave the best results at different weight fractions. However, 3 wt. % emerged as the weight fraction with optimum values.

No abstract

In this study, wear resistance and some selected physical properties of pawpaw–glass fiber hybrid reinforced epoxy composites were investigated. Two different layers of pawpaw stem—linear and network structures—were extracted and chemically modified. Hybrid reinforced composites were developed comparatively from the two fiber structures and glass fiber using hand lay-up in an open mold production process. The wear resistance was studied via the use of a Taber Abrasion Tester while selected physical properties were also investigated. The influence of the fiber structure on the properties examined revealed that network structured pawpaw fiber was the best as reinforcement compared to the linearly structured fiber. The addition of these vegetable fibers to epoxy resin brought about improved thermal conductivity and increased the curing rate while the wear resistance of the corresponding developed composites were enhanced by 3 wt% and 15 wt% of fibers from linear and network pawpaw fibers. It was noticed that linearly structured pawpaw fiber had its best result at 3 wt% while network structured pawpaw fiber had its best result at 15 wt%.

The demand for durable and sustainable eco-friendly materials in recent times has caused many researchers to consider the use of plant fibers in composite development. In this research, the suitability of treated pawpaw fiber as a substitute for glass fiber was considered. The pawpaw fiber was extracted from the plant stem by dew retting and treated before been incorporated into the epoxy matrix. Two distinct fiber structures in linear and network forms were identified, separated, and used for the development of the composites. The composites were produced by incorporating a fixed amount of pawpaw fiber with a varied amount of glass fiber within 3–15 wt% in epoxy-based polymer matrix after which mechanical and biodegradation tests were carried out on the developed samples. Fractured surface morphology was also observed using a scanning electron microscope. The results revealed that the fiber structures influence the properties of the material. While mechanical properties were mostly enhanced by treated linear structure pawpaw fiber, biodegradation was highly promoted by treated network structure pawpaw fiber. Tensile (except for strain), hardness, and flexural properties were enhanced by the linear-structured treated pawpaw fiber, while biodegradability, impact, and tensile strain were improved by the network-structured treated pawpaw fiber compared to the control sample.

No abstract

Natural fibres are biodegradable materials that contribute to the development of a “green” economy due to their numerous merits such as energy efficiency, ease of manufacturing, environmental friendliness, low cost, sustainability, and biodegradability. Natural fibres have lately become more appealing to technology and innovation as substitute materials for synthetic fibre-based composites due to these qualities. Several projects have also been undertaken to reveal the potential applications, economic and environmental benefits of natural fibres sourced from plants for polymer reinforcements. Among the commonly used fibres are banana and sisal fibres which form part of the reasons for their selection in this review. The justification for this is the environmental concerns in the modern days which have increased the demand for natural materials as suitable alternatives for synthetic reinforcements. Hence, this review reveals the impact of banana and sisal fibres as reinforcements in polymers on the environment, the possible future processing pathways, and applications.

This study investigates the hybrid effect of chemically modified sisal fiber and snail shell particles on the performance of polyester composites. The sisal fiber used was extracted by soil retting method and some portions were treated with potassium hydroxide (KOH) and sodium hydroxide (NaOH) solutions, respectively. The snail shell was calcined before grinding and sieving into particle size of ˂75 μm. The composites were developed using randomly dispersed open mould technique by varying the reinforcements between 2-10 wt. %. The particulate snail shell was analyzed with XRF where it was discovered that Mn and Ni were the major constituents while the developed composites were also subjected to different tests in accordance with the existing ASTM standards. The results revealed that the incorporation of sisal fiber and snail shell particles in the polyester matrix resulted in better tensile and flexural properties. The performance of the materials in moisture environment showed that chemically modified sisal fiber samples reduce the tendency for moisture absorption. The influence of the modification was best for samples from KOH treated fiber compared to NaOH treated fiber. Hence, it was discovered that snail shell/modified sisal fiber aid the enhancement of the performance of the developed composites.