Environmentally friendly and sustainable bark cloth for garment applications: Evaluation of fabric properties and apparel development

Ugandan bark cloth has been recognised by UNESCO as a masterpiece of the ‘Intangible Cultural Heritage of Humanity’, to protect the knowledge, traditions and livelihoods associated with its production. Bark cloth is a non-woven, fibrous textile that has been produced from the wild fig or mutuba tree (Ficus natalensis) by the Baganda people of southern Uganda for hundreds of years. A typical bark cloth has a rich, terracotta colour and is worn by kings and chiefs during coronations, religious ceremonies and cultural gatherings, as well as for funeral shrouds. Due to the growing awareness and the need to reduce the environmental impact of textiles, there is a pressing rationale to use natural materials or fibres in fashion clothing in recent years as designers and practitioners embrace environmentally sustainable raw materials and promote traditional craftsmanship. Various properties and significance of bark cloth from cultural, ethical, technical and aesthetic perspectives to determine its feasibility as a sustainable fashion textile was explored. The potential of bark cloth specifically in relation to the characteristics of luxury fashion (craftsmanship, quality, rarity, heritage and storytelling), through using techniques that include embroidery, appliqué, gilding, laser cutting, natural dyeing and fusing is highlighted. The bark cloth was investigated for its practical suitability for apparel end use. Various fabric tests were conducted to determine its performance including fabric drape, stiffness, surface morphology, and tearing strength. The bark cloth was subjected to CO2 laser etching and sublimation printing to incorporate surface patterns and attenuated total reflectance Fourier transform infrared spectroscopy [ATR-FTIR] was used to monitor the loss of fibres. Based on the trials, an optimum set of parameters were identified to use laser and sublimation printing. Raw bark cloth was stiff when heat-pressed, so it was fused with various fusible interfacing fabrics [A,B, and C] to enhance drape, texture, handle and strength. Results indicated that bark cloth when fused with woven interfacing [C] improved its strength [warp direction aligned with fabric grain] by approximately six times [330 N] the strength of bark cloth [57 N]. Fabric drape increased marginally [1.0–3.0%] when fusing with the interfacing, however it offered better handle when making the garment. A basic test garment (size 12 female full-sleeve top) was developed with the fused bark cloth that offered good drape and its shape and fit were evaluated on a mannequin. Outcomes indicated that bark cloth could be satisfactorily developed into outer garments with specific treatment

Flow micro-calorimetry and diffuse reflectance Fourier transform infrared spectroscopy studies in filled polyurethane adhesives by using dimethyl adipate as a model compound

Interactions between nano-scale filler particles (precipitated calcium carbonate, carbon black and fumed silica) and model compounds (dimethyl adipate and butan-2-one) are quantified using flow micro-calorimetry (FMC) and diffuse reflectance Fourier transform infrared spectroscopy (DRFTIRS). Carbonyl groups of dimethyl adipate interact strongly with silanol groups on the fumed silica surface but weakly with the uncoated precipitated calcium carbonate. In general, higher surface area loading imparts high level of adsorption because of the nanofiller has more adsorption sites. Carbon black is an exception likely due to the less accessible surface groups and the presence of relatively important amount of micropores. © 2013 Elsevier Ltd

The physicochemical investigation of hydrothermally reduced textile waste and application within carbon-based electrodes.

From Europe PMC via Jisc Publications RouterHistory: ppub 2019-04-01, epub 2019-04-10Publication status: PublishedTextile waste is on the rise due to the expanding global population and the fast fashion market. Large volumes of textile waste are increasing the need for new methods for recycling mixed fabric materials. This paper employs a hydrothermal conversion route for a polyester/cotton mix in phosphoric acid to generate carbon materials (hydrochars) for electrochemical applications. A combination of characterization techniques revealed the reaction products were largely comprised of two major components. The first is a granular material with a surface C : O ratio of 2 : 1 interspersed with phosphorous and titanium proved using energy dispersive X-ray spectroscopy, and the other is a crystalline material with a surface C : O ratio of 3 : 2 containing no phosphorous or titanium. The latter material was found via X-ray diffraction and differential scanning calorimetry to be terephthalic acid. Electrochemical experiments conducted using the hydrochar as a carbon paste electrode demonstrates an increase in current response compared to carbon reference materials. The improved current responses, intrinsically related to the surface area of the material, could be beneficial for electrochemical sensor applications, meaning that this route holds promise for the development of a cheap recycled carbon material, using straightforward methods and simple laboratory reagents

Effect of polymerization catalyst technology on the melt processing stability of polyethylenes, Part 3: Additives blends performance

© 2014 Society of Plastics Engineers. This article considers the interaction between additives that occur during the stabilization process. The simultaneous effects of the additives and associated interactions on melt processing stability and processing discoloration were of particular interest. Melt stability is an important factor to consider because physical changes in the processed polymer can occur during the compounding and fabrication steps. Furthermore, discoloration is one of the most important problems affecting commercial polymers. Most discoloration manifests itself as yellowing, especially in the case of polyolefins. Although yellowing can often be associated with degradation processes caused by various agents, such as light or heat, this is not always the case; yellowing can also be due to the interaction of additives in the stabilizer packages. Blends of primary antioxidants (AOs), secondary AOs, and hindered amine light stabilizers have been studied with the intention of further improving stabilization performance together with cost reduction of the stabilized polymer. Although synergism between AOs and a stabilizer is fairly common, antagonism was also observed in terms of melt flow protection and in color stability in some of the AOs tested. The effects of a range of thermal and light stabilizers on the melt stability (investigated via multiple pass extrusion) and color stability of three different polyethylenes (PEs) were examined. The PEs varied in terms of the catalyst system used to synthesize the polymers and included a high-density polyethylene (HDPE) produced by using a chromium-based Phillips catalyst and two linear low-density polyethylenes (LLDPEs) produced via chromium-based metallocene and titanium-based Ziegler-Natta catalysts. The apparent lack of influence of polymerization catalyst system on the mode of stabilizer interaction should lead to the reassessment of stabilizer formulation strategies in relation to PE type/catalyst system and associated commercial/economic considerations. J. VINYL ADDIT. TECHNOL., 22:117-127, 2016

Differential engulfment of Staphylococcus aureus and Pseudomonas aeruginosa by monocyte-derived macrophages is associated with altered phagocyte biochemistry and morphology

Knowledge of changes in macrophages following bacterial engulfment is limited. U937-derived macrophages were incubated with Staphylococcus aureus or Pseudomonas aeruginosa. Morphological and biochemical changes in macrophages following host-pathogen interactions were visualized using Scanning Electron Microscopy (SEM) and Fourier-Transform Infrared Spectroscopy (FTIR) respectively. Principal Component Analysis (PCA) was used to assess the variability in the FTIR spectra. Following host-pathogen interactions, survival of S. aureus was significantly lower than P. aeruginosa (P 99 % of variability in the FTIR spectra explained by the first two principal components. These findings demonstrated that there were clear morphological and biochemical changes in macrophages following engulfment of two different bacterial types suggesting that the biochemical components of the bacterial cell wall influenced the biochemical characteristics and hence the morphology of macrophages in distinct ways

Interfacial surface properties of compression moulded hydrolysed Polyvinyl Acetate (PVAc) using different release materials

Understanding the effect surface production has on polymer properties is important in the design of advanced materials. The aim of this study was to determine how the moulding process affected the rate of hydrolysis and the topography, chemistry and physicochemistry of PVAc moulded, hydrolysed surfaces. Three different mould surface materials were used to produce compression moulded PVAc sheets which were treated with aqueous NaOH at a range of concentrations. The Textile moulded sheet demonstrated the best hydrolysis results. The topography of the moulded sheets was transferred to the surfaces and the Kapton release sheet was visually smooth at lower magnification and demonstrated some pitting at higher magnification. The Teflon surface had features transferred from the coated stainless steel at lower magnifications and linear features at higher magnifications and the textile surface had a wrinkled appearance and irregularly spaced peaks. The release sheet used to mould the PVAc surfaces, affected the physicochemical parameters. The Kapton moulded surface demonstrated the most polar attributes and the Teflon surface the most dispersive. It was clear that the selection of the mould material had an influence on surface properties and hydrolysis of moulded PVAc. Such information is important for engineering design in industrial processes

Zeolite-embedded silver extends antimicrobial activity of dental acrylics

The insertion of prosthetic devices into the oral cavity affects the oral microflora and results in accumulation of microorganisms on the prosthetic surface. Such fouling of denture surfaces can lead to a number of oral diseases and consequently to the replacement of the denture. Here, we report the post-synthesis introduction of silver in zeolite-loaded dental acrylic (DAZ) resins that does not influence the mechanical or aesthetic properties of the DA resins, and provides them with a long-term antimicrobial activity. Na-FAU zeolite (2 wt%) was incorporated into DA resin, which was conventionally processed and cut into 10 mm x 20 mm x 3 mm coupons. The Na+ in the zeolite was then exchanged with Ag+ via immersion of the DAZ coupons in 0.01 M AgNO3 solution to obtain DAZ/Ag-treated coupons used in antimicrobial tests. Antimicrobial tests showed that the DAZ/Ag-treated coupons were active against Candida albicans (a reference and a clinically relevant strain), Streptococcus mutans and Fusobacterium nucleatum. Ag leaching tests on the Ag-charged coupons at 1, 2, 3, 4, 7, 14, 30 and 45 days of incubation in distilled water at 37 °C, indicated sustained release of silver. Antimicrobial tests using a reference Candida albicans strain showed that the leached coupons retained antimicrobial activity after 45 days immersion in distilled water, but, after 60 days incubation no antimicrobial activity was observed. Cytotoxicity assay results indicated that the DAZ/Ag-treated coupons showed no additional cytotoxicity compared to neat dental acrylic coupons