Textiles, Volume 2, Issue 1 (March 2022) – 10 articles

The expansion of clothing and textile industry and the fast fashion trend among consumers have caused a rapid global increase in textile waste in the municipal solid waste (MSW) stream. Worldwide, 75% of textile waste is landfilled, while 25% is recycled or reused. Landfilling of textile waste is a prevalent option that is deemed unsustainable. Promoting an enhanced diversion of textile waste from landfills demands optimized reuse and recycling technologies. Reuse is the more preferred option compared with recycling. Various textile reuse and recycling technologies are available and progressively innovated to favor blended fabrics. This paper aims to establish reuse and recycling technologies (anaerobic digestion, fermentation, composting, fiber regeneration, and thermal recovery) to manage textile waste. Improved collection systems, automation of sorting, and discovering new technologies for textile recycling remains a challenge. Applying extended producer responsibility (EPR) policy and a circular economy system implies a holistic consensus among major stakeholders. Full article

In this research, we focused on testing the physical and mechanical properties of the developed polyacrylonitrile (PAN) composite nanofibers with succinite (Baltic amber) and SiO₂ particles using standard methods of nanofiber testing (physical and mechanical properties). Polyacrylonitrile composite nanofibers (based on the electrospinning method) were coated on an aluminum substrate for structural investigation. SEM was used to determine the average fiber diameter and standard deviation. The mechanical properties of the fibers were determined using a universal testing machine (NANO, MTS). We observed that constant or decreased levels of crystallinity in the ultrafine composite nanofibers led to the preservation of high levels of strain at failure and that the strength of nanofibers increased substantially as their diameter reduced. Improvements in PAN composite nanofibers with succinite and SiO₂ nanopowder are feasible with continuous decreases in diameter. The drastically decreased strain at failure demonstrated a substantial reduction in viscosity (toughness) of the annealed nanofibers. Large stresses at failure in the as-spun nanofibers were a result of their low crystallinity. As a result, decreasing the diameter of PAN nanofibers from approximately 2 micrometers to 139 nanometers (the smallest nanofiber tested) resulted in instantaneous increases in the elastic modulus from 1 to 26 GPa, true strength from 100 to 1750 MPa, and toughness from 20 to 604 MPa. Full article

A new geometrical modeling tool has been developed to predict the elastic stiffness properties of 2D orthogonal and 2.5D woven interlock composites. The model estimates the change in performance due to changes in the ordering weaving parameters of the 2.5D weave architecture. Analysis results were validated compared to other models developed in published articles and the literature. Numerical analysis was performed to evaluate the accuracy of the results from the proposed models. These results demonstrate the effectiveness of the models presented by comparisons with experimental results, showing that the model could replicate the mechanical behaviors of 2D fabric and 2.5D interlock composite laminates for predicting 2D textile structures and 2.5D interlock composites with different types, shapes, and conditions. The model presented in this paper is able to replicate the behavior of woven composites of fiber reinforced with various types. Full article

Nanofiber-based nonwoven mats produced in electrospinning setups are usually very fragile, which often limits their applicability. Yarns have the potential to enable the incorporation of nanofibers into other materials using well-established techniques such as sewing, knitting, weaving and embroidering, thus broadening the application of nanofibers. Here, we review the development of continuous yarn electrospinning processes. Amongst several possible approaches, funnel-based collector systems have been widely adopted. Here, we summarize recent developments in the field and highlight studies providing visions on how to expand that field of research in future studies of continuous yarn electrospinning. Full article

The RTM (Resin Transfer Molding) manufacturing process is largely used for the fabrication of textile composites. During the forming phase, the deformations of composite reinforcements at the mesoscopic scale, such as the positions, orientations, and changes in the sections of deformed yarns, are essential to calculate the permeability of the reinforcement in the injection phase and evaluate the mechanical behaviors of the final products. However, the mesoscopic models of the forming simulation lead to a high computational cost due to the numerous yarns and their complex contacts, especially for thick reinforcements. In this paper, a macro-meso method for predicting the mesoscopic deformations of composite reinforcements with a reasonable calculation time is presented in this paper. The proposed multi-scale method allows for the linkage of the macroscopic simulation of reinforcements with the mesoscopic modelling of an RVE (Representative Volume Element) through a macro-meso embedded approach. Based on macroscopic simulations using a 3D hyperelastic constitutive law, an embedded mesoscopic geometry is first deduced. The macro-meso embedded solution can lead to excessive extensions of yarns. To overcome this inconvenience, a local mesoscopic simulation based on the macro-meso embedded analysis is carried out on a single RVE. Finally, the multi-scale forming simulations are investigated in comparison with the experimental results, illustrating the efficiency of the proposed method. Full article

Flexible textile strain sensors that can be directly integrated into clothing have attracted much attention due to their great potential in wearable human health monitoring systems and human–computer interactions. Fiber- or yarn-based strain sensors are promising candidate materials for flexible and wearable electronics due to their light weights, good stretchability, high intrinsic and structural flexibility, and flexible integrability. This article investigates representative conductive materials, traditional and novel preparation methods and the structural design of fiber- or yarn-based resistive strain sensors as well as the interconnection and encapsulation of sensing fibers or yarns. In addition, this review summarizes the effects of the conductive materials, preparation strategy and structures on the crucial sensing performance. Discussions will be presented regarding the applications of fiber- or yarn-based resistive strain sensors. Finally, this article summarizes the bottleneck of current fiber- or yarn-based resistive strain sensors in terms of conductive materials, fabrication techniques, integration and performance, as well as scientific understanding, and proposes future research directions. Full article

Deciphering how the dielectric properties of textile materials are orchestrated by their internal components has far-reaching implications. For the development of textile-based electronics, which have gained ever-increasing attention for their uniquely combined features of electronics and traditional fabrics, both performance and form factor are critically dependent on the dielectric properties. The knowledge of the dielectric properties of textile materials is thus crucial in successful design and operation of textile-based electronics. While the dielectric properties of textile materials could be estimated to some extent from the compositional profiles, recent studies have identified various additional factors that have also substantial influence. From the viewpoint of materials characterization, such dependence of the dielectric properties of textile materials have given rise to a new possibility—information on various internal components could be, upon successful correlation, extracted by measuring the dielectric properties. In view of these considerable implications, this invited review paper summarizes various fundamental theories and principles related to the dielectric properties of textile materials. In order to provide an imperative basis for uncovering various factors that intricately influence the dielectric properties of textile materials, the foundations of the dielectrics and polarization mechanisms are first recapitulated, followed by an overview on the concept of homogenization and the dielectric mixture theory. The principal advantages, challenges and opportunities in the analytical approximations of the dielectric properties of textile materials are then discussed based on the findings from the recent literature, and finally a variety of characterization methods suitable for measuring the dielectric properties of textile materials are described. It is among the objectives of this paper to build a practical signpost for scientists and engineers in this rapidly evolving, cross-disciplinary field. Full article

Integrative medicine is a rapidly growing specialty field of medical care that emphasizes the amalgamation of complementary therapies and conventional medicine. Aromatherapy, one of the complementary therapies, is a centuries-old tradition, used in many cultures and societies as an alternative to, or in conjunction with, conventional medicine. However, there is very little understanding of its therapeutic benefits in the scientific realm related to the correct dosage of essential oils, their delivery mechanism and their efficacy on human physiology in general. We reviewed studies published between 2011–2021 focused on aromatherapy and textiles, and explore “textile” materials as a possible carrier for essential oils in this paper. Due to their proximity to the biggest organ of the human body, textiles can potentially serve as a good delivery system for the therapeutic benefit of essential oils. After this rigorous review, we found gaps in the field. Therefore, we propose cross-disciplinary synergies for future research to fully understand the therapeutic efficacy of essential oils. Full article

This study performs an analysis of steam penetration through thermal protective fabric materials. Different, multilayered thermal protective fabrics were selected and tested in a laboratory-simulated steam exposure, and their steam protective performance (SPP) was measured in terms of the time required to generate second-degree burns on the bodies of wearers. Additionally, the total transmitted thermal energy (TTTE) through the fabrics during testing was measured. Through statistical analysis, it was established that fabric properties, namely air permeability and thickness, are the key factors that affect the SPP and TTTE; the relationship among the fabric properties, SPP, and TTTE is also summarized. Theoretically, it has been found that heat and mass (steam) transfer occur through fabrics in the course of steam exposure, which mainly affect the SPP and TTTE. This study could help textile/materials engineers to develop high performance thermal protective fabrics for the increased occupational health and safety of firefighters and industrial workers. Full article

The current research is focused on the design and development of auxetic woven structures. Finite element analysis based on computational modeling and prediction of axial strain as well as Poisson’s ratio was carried out. Further, an analytical model was used to calculate the same parameters by a foldable zig-zag geometry. In the analytical model, Poisson’s ratio is based on the crimp percentage, bending modulus, yarn spacing, and coefficient of friction. In this yarn, properties and fabric parameters were also considered. Experimental samples were evaluated for the actual performance of the defined auxetic material. Auxetic fabric was developed with foldable strips created in a zig-zag way in the vertical (warp) direction. It is based on the principle that when the fabric is stretched, the unfolding of the folds takes place, leading to an increase in transverse dimensions. Both the analytical and computational models gave close predictions to the experimental results. The fabric with foldable strips created in a zig-zag way in the vertical (warp) direction produced negative Poisson’s ratio (NPR), up to 8.7% of axial strain, and a maximum Poisson’s ratio of −0.41 produced at an axial strain of around 1%. The error percentage in the analytical model was 37.14% for the experimental results. The computational results also predict the Poisson’s ratio with an error percentage of 22.26%. Such predictions are useful for estimating the performance of auxetic woven structures in composite reinforcement. The auxetic structure exhibits remarkable stress-strain behavior in the longitudinal as well as transverse directions. This performance is useful for energy absorption in composite reinforcement. Full article