Effect of Chemical Treatment on Water Absorption Capability of Polyester Composite Reinforced with Particulate Agro-Fibres

This study determined effects of chemical treatment on the degradation of polyester composite reinforced with agro-fibres. The fibres, after being chemically treated with 1M of hydrogen peroxide, sodium hydroxide and potassium hydroxide solution, were sun-dried and pulverized. Screened particulate fibres obtained from 800 µm sieve were mixed with polyester resin in predetermined proportions. Water absorption test was carried out on the samples and it was observed that the treated fibres showed lower water absorption rates (degradation) as compared with the untreated fibres. The overall responses confirmed the chemical treatment adopted as suitable for pre-treatment of agro-fibres to forestall degradation. Keywords: Agro-Fibres, Chemical Treatment, Degradation, Water Absorption, Particulate, Polyester Composite

IMPACT OF ALKALINE TREATMENT ON THE CONSTITUENTS, STRENGTH AND MORPHOLOGICAL CHARACTERISTICS OF BANANA FIBER

The readily availability of natural fibers have made them to be less expensive compared to the synthetic fibers. Hence, highest substitute for synthetic fibers in composites development today is natural fibers. In this research, banana fiber was extracted by dew retting and treated with alkaline for surface modification and possibly strengthening. Both treated and untreated fibers were tested with universal tensile testing machine and examined their surface morphology with scanning electron microscopy. The banana fiber's ultimate tensile strength (UTS) was assessed as a function of fiber diameter, test length and testing speed. It was observed from the results that chemical treatment improved the tensile strength of the fiber while surface morphology was noticed to be rough due to the removal of some fiber constituents. Hence, it was discovered that alkaline treatment improved the fiber condition, thus, making the fiber a suitable substitute for synthetic fibers in composite development

Mechanical, wear and thermal conductivity characteristics of snail shell-derived hydroxyapatite reinforced epoxy bio-composites for adhesive biomaterials applications

This research investigates the effects of snail shell-based hydroxyapatite (HAp) reinforcements on the mechanical, wear, and selected physical properties of epoxy-based composites. The exploitation of these properties was aimed at assessing the suitability and efficiency of the developed bio-composites for adhesive biomedical applications. Snail shell wastes were sourced and processed to obtain (HAp) particles of ˂20 μm. The bio-derived hydroxyapatite-based epoxy composites were produced using the stir-cast method by mixing the hydroxyapatite with the epoxy resin and hardener before pouring into the moulds where they are allowed to cure. Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD) of the snail shell hydroxyapatite particles were carried out while mechanical, wear, and physical properties of the developed composites were evaluated. SEM images of the fracture surfaces were also examined. The results showed that enhancements occurred from the addition of snail shell-derived HAp to epoxy resin in the developed composites. The results revealed that most of the properties gave their optimum values when 15 wt.% reinforcement was used. At this weight fraction, optimum values were obtained which include 43 MPa for maximum flexural strength, 40HS for hardness, 40 J for impact, 0.35 W/mK for thermal conductivity, and 0.07 for wear index

Modern trends in recycling waste thermoplastics and their prospective applications: a review

Thermoplastics and thermosetting plastics are two major classes of polymers in that have recently become materials that are indispensable for humankind. Regarding the three basic needs of human beings—food, shelter, and clothing—polymers and polymer-based materials have gained pre-eminence. Polymers are used in food production, beginning with farming applications, and in the health sector for the development of various biomaterials, as well as in shelter and clothing for a variety of applications. Polymers are the material of choice for all modern-day applications (transportation, sporting, military/defence, electronics, packaging, and many more). Their widespread applications have created many negative challenges, mainly in the area of environmental pollution. While thermoplastics can be easily reprocessed to obtain new products, thermosetting plastics cannot; thus, this review focuses more on the use of waste from thermoplastics with less emphasis on thermosetting plastics. Hence, the review presents a concise summary of the availability of waste thermoplastics as raw materials for product development and the anticipated benefits. The prospects for waste thermoplastics and thermosetting plastics, the possibility of cleaning the environment, and the uncovering of opportunities for further research and development are presented. The limitations of the current methods of waste polymer recycling are highlighted with possible future prospects from newly introduced methods. With zero tolerance for polymer waste in our environments, potential uses for recycled thermosetting plastics are described. Waste polymers should be seen as potential raw materials for research and development as well as major materials for new products. Recycled polymers are expected to be processed for use in advanced materials applications in the future due to their availability. This review shows that the major source of environmental pollution from polymers is the packaging, hence the need to modify products for these applications by ensuring that most of them are biodegradable

Acetylation Treatment for the Batch Processing of Natural Fibers: Effects on Constituents, Tensile Properties and Surface Morphology of Selected Plant Stem Fibers

This work was on the comparative evaluation of the property effects obtainable when acetylation is applied to parts of selected agro fibers that are obtainable within common localities. The fibers were subjected to different concentrations of acetylation treatment at ambient temperature for 3 h. The physico-chemical, morphological, and tensile properties of the fibers were examined after the treatment. It was discovered from the results that the procedures variedly influenced the constituents of the fibers, their resulting tensile properties as well as their post-acetylation treatment surface morphology. The proportion of crystalline cellulose in the starting fibers greatly influenced their post treatment composition, behaviour and properties. The results show that plantain fibers had the highest aspect ratios, followed by banana fibers with values of about 1000 and 417, respectively. These fibers exhibited the least density and are thus potential plant fibers for composite development. Banana fiber had the least density of about 1.38 g/cm3 while that of DombeyaBuettneri fiber possessed the highest value of 1.5 g/cm3. There was significant enhancement in the hemicellulose content of Combretum Racemosum, while the lignin content of the plantain fibers was highly reduced. The treatment favoured the enhancement of the tensile properties in Combretum Racemosum fibers, which had enhanced tensile strength and strain at all compositions of the treatment. Optimum tensile strength and strain values of 155 MPa and 0.046, respectively, are achieved at 4% composition. Dombeya Buettneri fibers showed the highest ultimate tensile strength among the plant fibers in the untreated condition, which was gradually decreased as the concentration of the reagents was increased. Overall, 4% acetylation treatment is optimum for tensile properties’ enhancement for most of the natural fibers evaluated

Influence of Cow Bone Particle Size Distribution on the Mechanical Properties of Cow Bone-Reinforced Polyester Composites

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 m 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 m while toughness was highly enhanced by 6 and 8 wt% from 300 m. 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