Tamba Jamiru

A review on the sustainability of natural fiber in matrix reinforcement – A practical perspective:

Fiber reinforced composites have been used in several applications for several years and the market is continuously growing. It is known that the addition of fibers for reinforcing of matrix has advantages, especially the mechanical properties of the composites. Environmental and economic concerns are stimulating new research in the development of sustainable fiber for reinforcing polymer matrix. Particularly attractive are new materials in which a good part is based on natural and renewable resources, hence aggravating the environmental concerns that may result in the depletion and dwindling of wood resources from forest. This assessment report provides detailed world production of natural fiber and the inherent looming danger envisaged if attention is not shifted from its continuous usage. It has been stated that natural fibers are renewable and sustainable, but they are in fact, neither i.e. living plants are renewable and sustainable, from which natural fibers are taken, but not the fibers themselves. The US market reports that the composite market was 2.7 billion pounds sterling in 2006 and it is estimated to reach 3.3 billion pound sterling by 2012 with a 3.3% annual growth. Natural fiber market in the US experienced a 13% growth rate (275 million kilograms) between 1994 and 2004 and the demand for the natural fibers continues to rise. The average global annual market growth for natural fibers between 2003 and 2007 was 38%, while Europe saw the highest annual growth rate of 48%. This market was estimated at 0.36 million metric ton in 2007 and it is expected to reach 3.45 million metric ton in 2020. Fiber reinforced market is a multibillion dollar business and the natural fiber composites take a fair part of it.

Mechanical properties of sisal fibre-reinforced polymer composites: a review

Abstract There has been a growing interest in the utilization of sisal fibres as reinforcement in the production of polymeric composite materials. Natural fibres have gained recognition as reinforcements in fibre polymer–matrix composites because of their mechanical properties and environmental friendliness. The mechanical properties of sisal fibre-reinforced polymer composites have been studied by many researchers and a few of them are discussed in this article. Various fibre treatments, which are carried out in order to improve adhesion, leading to improved mechanical properties, are also discussed in this review paper. This review also focuses on the influence of fibre content and fabrication methods, which can significantly affect the mechanical properties of sisal fibre-reinforced polymer composites.

The use of polypropylene in bamboo fibre composites and their mechanical properties – A review

Bamboo fibre has gained significant interest as a sustainable reinforcement fibre in natural fibre/polymer composites, which is as a result of specific mechanical properties and being a biodegradable material compared to glass fibres. The article also gives a summary of how to improve the mechanical properties of bamboo fibre reinforced polypropylene (BFRP) composites as presented in various researches and the methodology of attaining these ultimate properties of bamboo fibres with polymeric matrices leading to improved BFRP. Mechanical properties of BFRP composites are improved by introducing coupling agent. Fibre treatment and nanoclay addition, in the right proportion, as reported have improved mechanical properties of BFRP composite.

Impact of Surface Modification and Nanoparticle on Sisal Fiber Reinforced Polypropylene Nanocomposites

The use of plant fibers, polymer, and nanoparticles for composite has gained global attention, especially in the packaging, automobile, aviation, building, and construction industries. Nanocomposites materials are currently in use as a replacement for traditional materials due to their superior properties, such as high strength-to-weight ratio, cost effectiveness, and environmental friendliness. Sisal fiber (SF) was treated with 5% NaOH for 2 hours at 70°C. A mixed blend of sisal fiber and recycled polypropylene (rPP) was produced at four different fiber loadings: 10, 20, 30, and 40 wt.%, while nanoclay was added at 1, 3, and 5 wt.%. Maleic anhydride grafted polypropylene (MAPP) was used as the compatibilizer for all composites prepared except the untreated sisal fibers. The characterization results showed that the fiber treatment, addition of MAPP, and nanoclay improved the mechanical properties and thermal stability and reduced water absorption of the SF/rPP nanocomposites. The tensile strength, tensile modulus, and impact strength increased by 32.80, 37.62, and 5.48%, respectively, when compared to the untreated SF/rPP composites. Water absorption was reduced due to the treatment of fiber and the incorporation of MAPP and nanoclay.

Electrical Conductivity of Cu and Cu-2vol.% Nb Powders and the Effect of Varying Sintering Temperatures on their Mechanical Properties Using Spark Plasma Sintering

The growing demand for relatively inexpensive non-hazardous copper alloys with a good combination of electrical conductivity and high strength has led to increasing researches on Cu-Nb alloys for their excellent predictions over Cu-Be alloys. Cu-2vol.% Nb was produced using spark plasma sintering and the effect of the additive on its electrical conductivity, densification, hardness, corrosion resistance and wear resistance were investigated. It was observed that the additive improved the electrical conductivity of Cu powder from 0.28 to 5.89 S/m within 19–406 ∘C. Relative densities of 97.08% for Cu-2vol.% Nb and 97.33% for pure Cu were obtained at 600 ∘C, while at 650 ∘C, they were 96.08 and 96.82% respectively. The microhardness values were 77 and 72 Hv0.1at 600 ∘C, while at 650 ∘C, they were 83 and 66 Hv0.1 for Cu-2vol.% Nb and pure Cu respectively. The corrosion potential of Cu-2vol.% Nb was noble with a lower anodic current density, suggesting better corrosion resistance at 600 ∘C. Cu-2vol.% Nb showed a better wear resistance at 600 ∘C and an improved electrical conductivity at 650 ∘C.

Development of Lightweight Insulation Body for Refrigerated Vehicles by Using Composite Materials

Energy demand in refrigerated vehicles account for about 5% of fossil fuel consumption globally and this percentage is expected to rise as perishable raw food continue to enjoy significant patronage of refrigerated vehicles which provide low temperature condition for its sustenance. Sustaining the shelf life of fresh food remains a herculean task to most farmers as cold chain must remain unbroken in order to maintain the quality of fresh food. The concept of this research is to reduce energy consumption in refrigerated vehicles through lightweight insulated panel as this medium could effectively reduce the payload of the entire vehicle. Part of the progress made in this work, is to develop five different composite cover sheet for insulated panel using fibre loading and orientation as manufacturing parameters and results show that the oriented reinforced composite materials offer significant weight reduction compared to unoriented composite cover sheet. The panel weight of these new materials were estimated using all the conceptual parameters of a refrigerated vehicle and the results indicate that composite reinforced with 10%wt. of fibre at 30o orientation in the matrix, offers the best panel weight reduction with 5.2380kg/m2 and 6.7380kg/m2 for 50mm and 100mm insulation thicknesses, respectively.

EXPLORING THE THERMAL PROPERTIES OF FLY ASHED-BASED GEOPOLYMER MATERIALS FOR COOLING APPLICATION IN BUILDINGS

Fly ash materials are the by-products of coal combustion process and the volume of this waste alone, accounts for about 80% of the total waste volume from a coal power plant. Part of the reclamation strategy of fly ash material is highly noticeable in the additives for cement production and this approach has recorded significant progress in view of its negative impact on the environment and also the process is generally cleaner due to the significantly low CO2 emission. In light of the above, a comprehensive and detailed study is therefore needed to explore some of inherent properties of fly ash material for passive cooling in buildings and its adjoining area. Energy consumption in buildings is projected to account for ~50% of world energy demand by 2050 and the underlying point of this research is to x-ray the low thermal conductivity of fly ash geopolymer materials for possible application in passive cooling of buildings and the conclusion drawn from this work may be explored by researchers for further study.

Energy Conservation in Refrigerated Vehicles through Prospective Light Weight Insulated Panel

Sustaining the shelf life of fresh food remains a herculean task to most farmers as cold chain must remain unbroken in order to maintain the quality of fresh food. The concept of this research is to reduce energy consumption in refrigerated vehicles through light weight insulated panel as this medium could effectively reduce the payload of the entire vehicle. Part of the progress made in this work, is to develop five different composite cover sheet for insulated panel using fibre loading and orientation as manufacturing parameters and results show that oriented reinforced composite materials offer significant weight reduction compared to un-oriented composite cover sheet. The panel weight of these new materials were estimated using all the conceptual parameters of a refrigerated vehicle and the results indicate that composite reinforced with 10%wt. of fibre at 30o orientation in the matrix, offers the best panel weight reduction with 5.2380Kg/m2 and 6.7380Kg/m2 for 50mm and 100mm insulation thicknesses, respectively.

Analysis of Overall Heat Transfer Coefficient of Composite Panels for Thermal Insulation

Heat infiltration through the external wall of refrigerated vehicles has been a concern to food industries considering high thermal load required to sustain unbroken cold chain. In this research, experiments were carried out with known fibres contents laid out at various orientations and the effect on the heat transfer measured. The results indicate that the estimated overall heat transfer coefficient of the composite reinforced with 10%wt. of fibre at 0o orientation (G10E) offers the lowest U value of 0.386950 W/m2K and 0.196680 W/m2K for 50 mm and 100 mm insulation thicknesses respectively. The effect of fiber orientation in the composite panel in energy saving was to a large extent minimal when compared to the un-oriented composite panel