Textiles, Volume 4, Issue 3 (September 2024) – 9 articles

This research developed shoe soles using a biodegradable and renewable composite made of King Oyster mushroom mycelium. An exploratory approach was used to develop biodegradable shoe prototypes using the mushroom mycelium composite as the midsoles. An online survey was conducted to evaluate the consumer acceptance of the shoe prototypes and a wear test with undergraduate college students was conducted to evaluate the consumer acceptance, wearability, and comfort of the shoe prototype. The survey results indicated that consumers liked the new sustainable footwear and were likely to purchase it. Indian consumers liked the new shoes more and would be more willing to purchase the new shoes than the U.S. consumers. The young age group would be more willing to buy this sustainable shoe prototype than the old age group. The consumers who were frequent consumers of sustainable products, willing to pay more for an environmentally friendly product, and cared about the environment were more likely to purchase this sustainable shoe prototype. The wear test with a small sample of four college students had split opinions on the comfort and wearability of the shoes. Still, all of them liked the concept of shoe materials and biodegradable shoes made from renewable materials. Full article

Composites of textile fabrics and 3D-printed layers have been investigated thoroughly during the last decade. Usually, material extrusion such as the fused deposition modeling (FDM) technique is used to build such composites, revealing challenges in preparing form-locking connections between both materials due to the highly viscous polymer melt, which can hardly be pressed into textile fabrics. Resins used for 3D printing by vat photopolymerization, i.e., for stereolithography (SLA), are less viscous and can thus penetrate deeper into textile fabrics; however, fixing a textile on the printing bed that is fully dipped into the resin is more complicated. Here, we present one possible solution to easily fix textile fabrics for SLA printing with consumer printers according to the digital light processing (DLP) sub-method. Also, we show the results of a study of the mechanical properties of the resulting textile/polymer composites, as revealed by three-point bending tests. Full article

Multifunctional composites and smart textiles are an important advancement in material science, offering a variety of capabilities that extend well beyond traditional structural functions. These advanced materials are poised to revolutionize applications across a wide range of industries, including aerospace, healthcare, military, and consumer electronics, by embedding functionalities such as structural health monitoring, signal transmission, power transfer, self-healing, and environmental sensing. This review, which draws on insights from various disciplines, including material science, engineering, and technology, explores the manufacturing techniques employed in creating multifunctional composites, focusing on modifying textiles to incorporate conductive fibers, sensors, and functional coatings. The various multifunctional capabilities that result from these modifications and manufacturing techniques are examined in detail, including structural health monitoring, power conduction, power transfer, wireless communication, power storage, energy harvesting, and data transfer. The outlook and potential for future developments are also surveyed, emphasizing the need for improved durability, scalability, and energy efficiency. Key challenges are identified, such as ensuring material compatibility, optimizing fabrication techniques, achieving reliable performance under diverse conditions, and modeling multifunctional systems. By addressing these challenges through ongoing research and further innovation, we can significantly enhance the performance and utility of systems, driving advancements in technology and improving quality of life. Full article

Textiles are composed of different types of fibers; thus, different processes for end-of-life recovery are currently applied. After collection, a prior sorting process is essential to classify the textiles and assess their quality in order to ensure that the best available technology is selected, with mechanical recycling being the most widespread and mature. Nevertheless, it still has important limitations as it is not suitable for the treatment of all fibers, especially those of non-organic origin and blends. On the other hand, chemical recycling appears to be a necessary technology to valorize the fibers that cannot be reused or mechanically recycled and to avoid landfilling. This article aims to provide an overview of the available technologies in the field of textile waste recycling, including collection, pretreatment, and mechanical and chemical recycling processes. Each technology is described identifying pros and cons, and a techno-economical assessment is presented including technology readiness levels (TRLs), investments, and costs. European and Spanish regulations and policies on textile waste are analyzed to identify the trends and directions the sector is moving towards. Full article

The increasing demand for environmental and sustainable materials has motivated efforts to fabricate biocomposites as alternatives to conventional synthetic fiber composites. However, biocomposite materials have some drawbacks such as poor mechanical resistance, fiber/matrix incompatibility, low thermal resistance and high moisture absorption. Extensive research has been conducted to address these challenges, in terms of the sustainable production, serviceability, reliability and properties of these novel biocomposites. Silk fibers have excellent biocompatibility and biodegradability along with moderate mechanical properties, while flax fibers have a high specific strength and modulus. The combination of the silk fiber with moderate modulus and stiffness with flax fibers with high specific strength and modulus allows the modulation of the properties of silk using the intra- and inter-hybridization of both fibers. In this study, silk and flax fibers are combined in different arrangements, totaling eight different composites; the quasi-static mechanical properties and dynamic mechanical thermal analysis are discussed, focusing on the structure versus relationship properties, with the aim of corroborating the freely available data from literature. The main findings indicated that the synergic effect of the flax fiber and silk fiber leads to a tailormade composite with a low cost and high performance. Full article

Electronic textiles (e-textiles) merge textiles and electronics to monitor physiological and environmental changes. Innovations in textile functionalities and diverse applications have propelled e-textiles’ popularity. However, challenges like connection with external devices for signal processing and reliable interconnections between flexible textiles and rigid electronic circuits persist. Wearable connectors enable the effective communication of e-textiles with external devices. Factors such as electrical functionality and mechanical durability along with textile compatibility are crucial for their performance. Merging the rigid connectors on the flexible textiles requires conductive and flexible interconnects that can bridge this gap between soft and hard components. This work focuses on designing two-part detachable mechanical snap connectors for e-textiles. The textile side connectors are attached to the data transmission cables within the textiles using three interconnection techniques—conductive epoxy, conductive stitches, and soldering. Three types of connectors were developed that require three detaching or unmating forces (low, medium, and high). All connectors were subjected to 5000 mating–unmating cycles to evaluate their mechanical durability and electrical performance. Connectors with low and medium unmating forces exhibited a stable performance, while those with high unmating forces failed due to wear and tear. Conductive stitches maintained better conductance as compared to conductive epoxy and soldering methods. Full article

Due to the continuous optimization of cutting plans, the cotton scrap size resulting from the cutting of components for clothing production (post-industrial residues) is often considered insufficient to obtain fibres with the proper length to produce a new yarn through mechanical recycling processes; so it is important to search for other applications for these wastes. In this context, small pieces of cotton were submitted to a shredding process to obtain recycled fibres. Cotton small pieces and recycled fibres were then submitted to a refining process to achieve refined fibres. Using these materials alone and in blends with refined and unrefined bleached eucalyptus kraft pulp (BEKP), wet-laid nonwovens were developed and characterized. An analysis of the results revealed that the replacement of unrefined BEKP by 70% cotton waste fibres in wet-laid nonwovens, reducing the use of virgin raw material, enhances the structures’ mechanical properties by 80% and 14%, for small pieces or recycled fibres, respectively. Additionally, refining small pieces of cotton seems to be more promising than refining recycled fibres, because less steps are required to obtain wet-laid nonwovens with better mechanical properties. These results highlight the potential of this approach to be explored further for different products and end applications. Full article

With the substantial growth of the smart textiles market, electrical properties are becoming a basic requirement for most of the advanced textiles used in the development of wearable solutions and other textile-based smart applications. Depending on the textile substrate, the test method to determine the electrical properties can be different. Unlike smart fibers and yarns, the characterization of the electrical properties of fabrics cannot be tested between two connection points because the result would not represent the behavior of the entire fabric, so the electrical properties must be related to an area. The parameters used to characterize the electrical properties of the fabrics include resistance, resistivity, and conductivity. Although all of them can be used to indicate electrical performance, there are significant differences between them and different methods available for their determination, whose suitability will depend on the function and the textile substrate. This paper revises the main parameters used to characterize the electrical properties of conductive fabrics and summarizes the most common methods used to test them. It also discusses the suitability of each method according to several intervening factors, such as the type of conductive fabric (intrinsically or extrinsically conductive), its conductivity range, other fabric parameters, or the final intended application. For intrinsically conductive woven fabrics, all the methods are suitable, but depending on the requirements of conductivity accuracy, the contact resistance from the measuring system should be determined. For intrinsically conductive knitted fabrics, two-point probe, Van der Pauw, and eddy current methods are the most suitable. And for intrinsically conductive nonwoven fabrics, two-point probe and four-point probe methods are the most appropriate. In the case of extrinsically conductive fabrics, the applied method should depend on the substrate and the properties of the conductive layer. Full article