Extraction and Characterization of Cellulosic Fibers from Jenfokie and Doby Stems: Effect of Extraction Methods on Physicochemical, Mechanical, and Thermal Properties

This experimental study aims to explore natural lignocellulosic fibers from Jenfokie and Doby plants. The effect of the fiber (water-retted and non-retted) extraction methods on physical, mechanical, thermal, chemical, and crystallinity properties were experimentally investigated for fibers collected from the eastern highlands of Ethiopia. The chemical composition (cellulose, hemicellulose, lignin, extractives, etc.) was determined after different treatment processes. The tensile strength maximum of up to 72 cN/tex and 56 cN/tex, and cellulose content up to 85% and 81% were obtained for Jenfokie and Doby retted extracted fibers, respectively. There was small difference lignin extracted by Klason method and the alkaline hydrogen peroxide (APH) method. Each step-wise extracted fiber was characterized to cognize the intrinsic changes during the multi-step extraction process. The diameters were determined by Optical Microscope (OM), the removal of non-cellulosic materials by Fourier Transform Infrared (FT-IR) spectroscopy, the thermal stability (up to 375°C) by thermogravimetry (TGA), and the crystallinity index (up to 73%) by using X-ray Diffraction (XRD). An improvement in cellulose content, density, moisture absorption, tensile strength, thermal stability, and crystallinity of Jenfokie (unstudied or new) and Doby plant retted fibers would be promising for composite and textile materials

Application of Quality Function Deployment in Customer Oriented Footwear Development Process

The main purpose of this study was to develop the house of quality in footwear development process. The study was conducted using quantitative research method. Both primary and secondary data sources were used. The primary data sources were sampled using purposive sampling method. The tools used for collecting the data were informant interview and questionnaire. The secondary data were collected from previous research outputs that are related to the application of quality function deployment in footwear development process. The collected data were analyzed using Microsoft Excel 2016 and QFD Capture Professional Edition 4.2.20. The analysis results revealed that the footwear produced by Ethiopian companies fared below par in comparison to the footwear produced by Chinese and European companies in terms of customer and technical perspectives. Therefore, Ethiopian footwear manufacturing companies shall use the prioritized customer and technical requirements in order to develop customer oriented footwear

Physical and mechanical behavior of aluminum-magnesium alloy matrix hybrid composite fabricated through friction stir consolidation process

Nowadays metal matrix composite materials are preferable in automotive and aerospace industries due to their mechanical properties and essentially attractive strength to weight ratios. However, their availability in use is limited because of their manufacturing method difficulty and process extravagancy. The aim of this research was to fabricate metal matrix hybrid composite through a novel approach thermo-mechanical method called friction stir consolidation (FSC) process. XRD result witnessed the presence of SiC, ZrO 2 , and AZ61 alloy phases. Different compositions of AZ61, SiC, and ZrO 2 powder were taken into consideration and the progression of the FSC process were examined through properties of compressive strength, hardness, density, and porosity. For instance, the compressive yield strength of composition 85%Vol. of AZ61, 10%Vol. of ZrO 2 , and 5%Vol. of SiC accounts 164.2 MPa with an acceptable 2.2451 g/cm 3 and 0.593% density and porosity respectively. However, when the strength to weight ratio was taken into consideration, 95%Vol. of AZ61, 2.5%Vol. of ZrO 2 , and 2.5%Vol. of SiC composition attained highest strength to weight ratio value. Additionally, the compressive yield strength value increased directly proportional with the ZrO 2 volumetric composition. Likewise, the fractured surface of sample acquired highest strength to weight ratio was examined through SEM Fractography analysis

Extraction and Characterization of Fiber and Cellulose from Ethiopian Linseed Straw: Determination of Retting Period and Optimization of Multi-Step Alkaline Peroxide Process

Flax is a commercial crop grown in many parts of the world both for its seeds and for its fibers. The seed-based flax variety (linseed) is considered less for its fiber after the seed is extracted. In this study, linseed straw was utilized and processed to extract fiber and cellulose through optimization of retting time and a multi-step alkaline peroxide extraction process using the Taguchi design of experiment (DOE). Effects of retting duration on fiber properties as well as effects of solvent concentration, reaction temperature, and time on removal of non-cellulosic fiber components were studied using the gravimetric technique, Fourier transform infrared (FTIR) spectroscopy and thermal studies. Based on these findings, retting for 216 h at room temperature should offer adequate retting efficiency and fiber characteristics; 70% cellulose yield was extracted successfully from linseed straw fiber using 75% ethanol–toluene at 98 °C for 4 h, 6% NaOH at 75 °C for 30 min, and 6% H2O2 at 90 °C for 120 min

Isolation and Characterization of Spherical Cellulose Nanocrystals Extracted from the Higher Cellulose Yield of the Jenfokie Plant: Morphological, Structural, and Thermal Properties

Scholars are looking for solutions to substitute hazardous substances in manufacturing nanocellulose from bio-sources to preserve the world’s growing environmental consciousness. During the past decade, there has been a notable increase in the use of cellulose nanocrystals (CNCs) in modern science and nanotechnology advancements because of their abundance, biocompatibility, biodegradability, renewability, and superior mechanical properties. Spherical cellulose nanocrystals (J–CNCs) were successfully synthesized from Jenfokie micro-cellulose (J–MC) via sulfuric acid hydrolysis in this study. The yield (up to 58.6%) and specific surface area (up to 99.64 m2/g) of J–CNCs were measured. A field emission gun–scanning electron microscope (FEG-SEM) was used to assess the morphology of the J–MC and J–CNC samples. The spherical shape nanoparticles with a mean nano-size of 34 nm for J–CNCs were characterized using a transmission electron microscope (TEM). X-ray diffraction (XRD) was used to determine the crystallinity index and crystallinity size of J–CNCs, up to 98.4% and 6.13 nm, respectively. The chemical composition was determined using a Fourier transform infrared (FT–IR) spectroscope. Thermal characterization of thermogravimetry analysis (TGA), derivative thermogravimetry (DTG), and differential thermal analysis (DTA) was conducted to identify the thermal stability and cellulose pyrolysis behavior of both J–MC and J–CNC samples. The thermal analysis of J–CNC indicated lower thermal stability than J–MC. It was noted that J–CNC showed higher levels of crystallinity and larger crystallite sizes than J–MC, indicating a successful digestion and an improvement of the main crystalline structure of cellulose. The X-ray diffraction spectra and TEM images were utilized to establish that the nanocrystals’ size was suitable. The novelty of this work is the synthesis of spherical nanocellulose with better properties, chosen with a rich source of cellulose from an affordable new plant (studied for the first time) by stepwise water-retted extraction, continuing from our previous study