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The quest for sound-absorbing materials that are not only environmentally friendly, but also sustainable is the foremost reason for natural fibre-acoustic materials. Bark cloth is a natural non-woven fabric that is largely produced from Ficus trees. An exploratory investigation of bark cloth a non-woven material and its reinforcement in epoxy polymer composites has been fabricated and investigated for the sound absorption properties so as to find the most suitable applications and also to see whether bark cloth can be used in some applications in place of man-made fibres. Three types of material species were investigated with their respective composites. The fibre morphology showed bark cloth to be a porous fabric that showed promising sound absorption properties at higher frequencies. The sound absorption results of four-layer material selections of Ficus natalensis, Ficus brachypoda and Antiaris toxicaria bark cloth showed sound absorption coefficient of 0.7; 0.71 and 0.91 at f > 6400 Hz, respectively. The bark cloth reinforced laminar epoxy composites had reduced sound absorption coefficients, which ranged from 0.1 to 0.35, which was attributed to decreased porosity and vibration in the bark cloth fibre network.

The present study aimed to develop wearable, electrically conductive hygienic electrodes and their use for Transcutaneous Electrical Nerve Stimulation (TENS) application. The development of electrodes was done in two stages. Firstly, the dispersion of conductive activated carbon particles was done into flexible elastomer followed by its silver electroplating. The Orthogonal Array Testing (OATS) technique was used to optimize the silver-plating recipe. The Fourier transform infrared spectroscopy (FTIR) analysis confirmed the impact of activated carbon by increase in intensity of stretching bands. To improve electrode properties in response to various human body movements, resistivity changes due to stretching and repeated extension were tested on conductive elastomers. Increasing the extension degree allowed a very minute change in electrical resistivity. Therefore, the resistivity can be considered almost constant within the 0-60 % stretch range. While, a notable increase in electrical resistivity was observed after 70 % of stretch. However, the resistivity of elastomers remained stable even after repetitive extension (for over 100 cycles). Conversely, no significant change in resistivity was observed over time when subjected to a constant current. Furthermore, to minimize the effect of skin electrode resistivity during electrotherapy, the range of different pressure was applied over the surface of electrodes. Minimum value of resistivity about 1 Ω.mm was obtained at 6 N/cm2 of applied pressure. Additionally, hygienic properties, such as antiviral, antibacterial and antifungal were examined using different pathogens to assess the impact of the deposited silver particles. In the end, the durability of electrodes against washing and rubbing was confirmed. The potential applications of prepared electrodes are in the field of electrostimulation and electrotherapy etc. [ABSTRACT FROM AUTHOR]

Emission of greenhouse gases and increasing global warming have posed serious threats to the environment and survival of mankind. Construction industry is amongst the leading polluters and currently traditional materials are being used at large scale to meet the increasing demand to construct new facilities. Concrete is a widely used material in construction industry and steel bars are often used as reinforcement. Cement being the main constituent of concrete and steel bars used in it require greater amount of energy. During the fabrication of concrete, an intensive amount of carbon dioxide (CO2) is emitted to the environment. The utilization of industrial waste (by-products) as a replacement of cement and textile waste as a reinforcement for cementitious composites represent one of the promising solutions. Use of industrial by-products not only address the waste disposal problem but also help in reducing energy demand for concrete production. This paper describes an over review on the efforts done in reducing dependence of traditional materials used in cementitious composites. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) presents significant promise as a biomaterial, boasting unique qualities such as exceptional cellulose purity, robust mechanical strength, heightened crystalline structure, and biodegradability. Several studies have highlighted specific effects, such as the impact of dehydration/rehydration on BC tensile strength, the influence of polymer treatment methods on mechanical properties, the correlation between microorganism type, drying method, and Young's modulus value, and the relationship between culture medium composition, pH, and crystallinity. Drying methods are crucial to the structure, performance, and application of BC films. Research findings indicate that the method used for drying can influence the mechanical properties of BC films, including parameters such as tensile strength, Young's modulus, and water absorption capacity, as well as the micromorphology, crystallinity, and thermal characteristics of the material. Their versatility makes them potential biomaterials applicable in various fields, including thermal and acoustic insulation, owing to their distinct thermal and mechanical attributes. This review delves into the thermal and mechanical behavior of bacterial cellulose aerogels, which are profoundly impacted by their drying mechanism. [ABSTRACT FROM AUTHOR]

Given their exceptional attributes, aerogels are viewed as a material with immense potential. Being a natural polymer, cellulose offers the advantage of being both replenishable and capable of breaking down naturally. Cellulose-derived aerogels encompass the replenish ability, biocompatible nature, and ability to degrade naturally inherent in cellulose, along with additional benefits like minimal weight, extensive porosity, and expansive specific surface area. Even with increasing appreciation and acceptance, the undiscovered possibilities of aerogels within the textiles sphere continue to be predominantly uninvestigated. In this context, we outline the latest advancements in the study of cellulose aerogels' formulation and their diverse impacts on textile formations. Drawing from the latest studies, we reviewed the materials used for the creation of various kinds of cellulose-focused aerogels and their properties, analytical techniques, and multiple functionalities in relation to textiles. This comprehensive analysis extensively covers the diverse strategies employed to enhance the multifunctionality of cellulose-based aerogels in the textiles industry. Additionally, we focused on the global market size of bio-derivative aerogels, companies in the industry producing goods, and prospects moving forward. [ABSTRACT FROM AUTHOR]

Thermal comfort properties of 3-Dimensional knitted spacer fabrics have been studied in order to replace the existing polyurethane foams in the car seat and back supports. The influence of different characteristics of spacer fabrics, like structure, areal density, thickness and density on thermo-physiological performance has been studied. The potential thermal behavior is identified with the support of the thermal conductivity and resistance evaluation. The air and water vapor permeability have been measured and analyzed in-order to study the breathable performance of spacer fabrics. Advance statistical evaluation and two-way analysis of variance is used to analyze the significance of various factors on required properties. The result shows that spacer fabric with a hexagonal net structure has more open structure on surface than lock knit fabrics, which results in highly permeable to air with good thermal conductivity. It is also observed that, the hexagonal net fabrics have the ability to pass more water vapor than the fabrics with lock knit structure on the surface. These findings are the important requirements for designing the car seats with required thermal comfort properties using 3D spacer fabrics. [ABSTRACT FROM AUTHOR]

The development of functional textile structures is important to improve noise attenuation of human life in automotives, residential and occupational environments. In this research, an attempt has been made to find the suitability of three-dimensional (3D) knitted spacer fabrics for sound absorption. Hence, an experimental and analytical investigation on the sound absorption behavior of warp knitted spacer fabrics was conducted. Due to their porous nature, interconnected pores, bulkier and 3D structure, the spacer fabrics have the ability to attenuate more sound energy than conventional materials. This research examined the acoustic properties of spacer fabrics in relation to material parameters such as thickness, density and surface structure and structural characteristics such as massivity, porosity, tortuosity and air flow resistivity. The sound absorption coefficient of the test samples was measured using the impedance tube method by ASTM E-1050 in the frequency range of 50–6400 Hz. The results showed that the acoustic insulation of spacer fabric improves with their thickness and massivity, reduction in their porosity, tortuous path and high air flow resistance. Advance statistical evaluation and two-way analysis of variance is used to analyze the significance of the combined effect of various factors on air flow resistivity and the noise reduction coefficient. These findings are important requirements for the design of spacer fabrics for noise control in the automobile upholstery, buildings, auditoriums, etc. [ABSTRACT FROM AUTHOR]

Bark cloth is a natural nonwoven fibrous fabric produced in Uganda from three species of trees: Ficus natalensis, Ficus brachypoda, and Antiaris toxicaria. The recently developed bark cloth composites has created a new class of textile composites which can find applications in interior automotive panels. Four bark cloth plies were utilized, the resin was infused using Vacuum Assisted Resin Transfer Molding (VARTM). Scanning Electron Microscopy was used to study the fabric's fiber morphology, surface functional groups were characterized using Fourier Transform Infrared. Overall, the static and the Dynamical mechanical analysis showed that the developed composites had a tensile strength ranging from 22 to 29 MPa whereas the flexural strength ranging from 45 to 100 MPa. The glass transition temperature of the composites was ranging from 53°C to 63°C. POLYM. COMPOS., 38:199-204, 2017. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Bark cloth fabric has been in production in Uganda since the thirteenth century. In a move to preserve its cultural heritage, the United Nations Educational, Scientific and Cultural Organization (UNESCO) proclaimed in 2005 that Ugandan bark cloth is a “Masterpiece of the Oral and Intangible Heritage of Humanity.” Plant fibers require surface treatment before aimed at impurity reduction and for enhancement of fiber to matrix adhesion in composites. An exploratory investigation of enzymatic and plasma treatment of bark cloth is reported. The morphology of the fabric was investigated using scanning electron microscope. Thermal behavior of the fabric was studied using thermogravimetric analysis and differential scanning calorimetry. Fourier transform infrared spectroscopy and ultraviolet–visible (UV–vis) spectrophotometer were used to evaluate the surface functional groups. Enzyme-treated fabrics were cleaner and thermally stable compared to plasma and untreated fabrics. [ABSTRACT FROM AUTHOR]

The United Nations Educational, Scientific and Cultural Organization (UNESCO) proclaimed in 2005 that Ugandan barkcloth largely produced from mutuba tree (Ficus natalensis) as a “Masterpiece of the Oral and Intangible Heritage of Humanity.” An exploratory investigation of barkcloth a nonwoven material produced through a series of pummeling processes from mutuba tree in Uganda is fronted as reinforcement for epoxy composite laminates. The fabric and composite morphology was investigated using scanning electron microscopy (SEM). The composite response to loading against temperature, time, and frequency was investigated using dynamical mechanical analysis (DMA). The results show that the developed composites are stable with considerable tensile strength and bending rigidity thus providing material engineers with the possibility of applying the material for semi-structural applications. [ABSTRACT FROM AUTHOR]

Sansevieria trifasciatais a common perennial plant which freely grows and widely found in homes, parks, and woodlands. In this research, we studied the morphology using Scanning Electron Microscope and Fourier Transform Infrared (FTIR); thermal properties using Thermogravimetric (TGA) and Differential Scanning Calorimetric (DSC) analyses; mechanical behavior through tensile tests of Sansevieria trifasciata fiber (STF) obtained from Butaleja in Eastern Uganda. Findings show that the fiber has an irregular cross-sectional shape with lumens in the center, the fiber diameter was between 80 and 120?m. TGA tests showed that the fiber is stable below 200°C with maximum cellulose decomposition temperature of 315°C. DSC showed that the fiber’s crystallization temperature was 310.5°C and lignin decomposition temperature of 372.7°C. The surface functional groups were majorly of cellulose, hemicelluloses, and lignin in direct correlation with research elsewhere on natural fibers. [ABSTRACT FROM PUBLISHER]

The United Nations Educational, Scientific and Cultural Organization in 2005 proclaimed that Ugandan barkcloth largely produced frommutubatree (Ficus natalensis) as a “Masterpiece of the Oral and Intangible Heritage of Humanity”. An exploratory investigation of thermo-physiological and comfort properties of barkcloth, a nonwoven material produced through a series of pummeling processes from mutuba tree in Uganda, is fronted. Barkcloth was extracted from theF. natalensistree in Nsangwa village, Buyijja parish in Mpigi district, Central Uganda. Thermal conductivity, thermal diffusivity, thermal absorptivity, thermal resistance, fabric thickness, and peak heat flow density were measured using an Alambeta device, whereas a Permetest device was used for the measurement of the moisture vapour permeability and evaporation resistance. The study was carried out under relative humidity of 40% and at a laboratory room temperature of 24°C and the results show that the thermal conductivity is in the range of cotton fabrics rendering barkcloth fromF. natalensis, a comfortable fabric. The lower value of thermal absorptivity of barkcloth compared to the value of cotton renders the fabric a warm feeling when in contact with the skin. Barkcloth had a higher moisture vapor permeability compared to cotton and other fabrics, meaning its clothing comfort properties are reasonable. [ABSTRACT FROM PUBLISHER]