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In our daily life, the temperature and washing parameters go unnoticed on the electrical properties of conductive yarns and woven fabrics. However, in many cases, these parameters play a crucial role in the use of conductive materials since they modify their electrical properties. It is critical to predict what this behaviour will be, as these washing and, in our temperature, parameters can improve or even deteriorate desirable properties in the materials, especially of sensors embedded textiles. The weight of the conductive samples was decreased up to 11% for silver-coated and 7.75% for gold-coated yarn after washing. The results suggest that the electrical resistance of yarns increases 1.6%, 8%, and 8.7% for silver-coated while 13%, 20%, and 21% increase in resistance value for gold-coated yarn after 1st, 2nd, and 3rd wash, respectively. The silver-coated yarn has better electrical conductance, and ageing does not affect the electrical resistance of both silver-coated yarns and fabrics till two washes and a slight change occurred after 3rd wash. The woven structure’s mass per unit area decreases up to 7.69% and 3.7% for silver-coated and gold-coated samples, respectively. Woven samples conductivity for silver-coated structures decreased 95% and 98% for gold-coated structures

Green composites have ecofriendly features that are technically and economically feasible while minimizing the pollution. It refers to the combination of degradable fibers mostly cellulosic materials and natural resins to develop green composites. Since mechanical performance of such structures is a concern for industry, by playing with the position and pattern of yarns in woven fabric, these properties can be optimized. This research focuses on the development and characterization of novel 3D woven jute/green epoxy composites having hybrid interlocking patterns. Four conventional derivatives of 3D woven fabrics i.e. orthogonal layer to layer (OLL), orthogonal through thickness (OTT), angle interlock layer to layer (ALL), angle interlock through thickness (ATT) and three novel 3D woven fabrics i.e. H1 (combination of OTT and ATT binder yarns), H2 (combination of OTT and ALL binder yarns), H3 (combination of orthogonal layer to layer warp and weft interlock called as bi-directional interlock) were developed using different binding patterns on dobby loom. Tensile, flexural, and short beam shear tests were performed to check the mechanical performance of the developed composites. OTT composite structure showed the highest values of tensile strength, modulus, and maximum force both in warp and weft directions as compared to the other 3D interlock structures, due to least interlacement/crimp of binder yarn. While ATT composite exhibited the highest value of flexural strength and modulus both in warp and weft directions due to through thickness angle binder yarns. H3 composite showed the highest values of force and short beam shear strength in warp direction.

The textile-based pressure sensors are an integral part of the wearable electronic textiles, that helps to measure the pressure/load applied to the sensor. These sensors are used predominantly for health and sports application, especially to monitor the blood pressure, heart rate or performance of muscles during exercise. The work done in this research is about the investigation of the response of a 3D woven fabric-based pressure sensor by varying the yarn interlacement pattern in 3 layered fabric. Four samples were produced using a 3D weaving technique, with two types of yarns i.e. polyester/cotton (59 tex) and multifilament steel (55.5 tex). The weave design of face and back layer of the three-layered structure was kept 1/1 plain (P), while the weave design of middle layer was changed to plain (P), matt (M), twill (T) or satin (S), resulting in structures PPP, PMP, PTP, and PSP respectively. Working of pressure sensor was evaluated in terms of resistance offered by structure, both under static and dynamic loading. The dynamic load was applied by the compression and subsequent relaxation, i.e. under incremental loading followed by decremental unloading. All the structures showed variation in resistance in response to applied load showing potential being used as a pressure sensor. The structures PPP, PMP, and PSP behaved as a pressure sensor up to 500 grams while the efficient sensor was PTP (plain/twill/plain) with activity up to a load of 5500 grams. A statistical model was developed for the structure PTP, correlating the resistance with the applied load. The developed sensors can also be produced inside the fabrics or can be embedded inside garments.

In recent times, auxetic woven structures gained considerable attention from the researchers due to their excellent impact properties in high-performance areas. Researchers have done much work on t...

Three-dimensional woven spacer composites have great potential for use in different parts of automobiles and construction application due to their better mechanical performance. In literature, time-dependent compression and recovery behavior of three-dimensional woven spacer composites was not studied. In this study, three-dimensional woven spacer composites (three thickness levels) were evaluated under static and dynamic (time-dependent) compression and recovery. The static compressive strength of composites was reduced with the increase in sample thickness. Also, the highest amount of energy was absorbed during the fracture of 4 mm (Comp4) thick composite, followed by 10 mm (Comp10) and 20 mm (Comp20) thick composites. Compressibility (%) and resiliency (%) was highest in Comp4 but recovery (%) was a bit lower as compared to the Comp10 and Comp20, while recovery (%) was highest in 10 mm thick composite as compared to the 4 mm and 20 mm thick samples. Moreover, higher value of permanent deformation in thickness with time was observed in Comp20 showing higher creep followed by Comp4 and Comp10. Furthermore, Comp4 showed the highest values of work done during cyclic compression loading–unloading testing, presenting highest toughness.

Back pain is a commonly known problem for drivers and passengers traveling in long route vehicles, especially buses and trucks. The problem becomes more severe for people suffering from bedsores. The current embodiment is a step toward addressing this problem. This method helps to regulate blood flow and provide comfort to the drivers and bedsore patients. Pneumatic cylinder and 24 semi-circular designed aluminum buds are used in the assembly that moves up and down along with the comforter foam and sheet to serve the purpose. This design is an active way of providing comfort and has significantly helped in reducing back and lower body pain. A survey was conducted by 100 participants to analyze the comfort of the current embodiment. The age of these participants was divided into two categories. Results showed that comfort varies with age and pressure. It was concluded from the survey that young people from 20 to 30 years appreciate high pressure, whereas elderly people from 30 to 50 years like low pressure. The results from analysis of variance were found to be significant with feedback results. This system is also helpful in regulating blood flow. It was concluded that most people like high pressure and the first pattern.

Three-dimensional (3D) woven spacer fabric is produced by connecting two woven fabric layers with the vertical pile yarns in the center part. Their composites have great potential for use in construction, automotive, marine, and aerospace applications due to outstanding mechanical properties. In this paper, 3D woven spacer fabrics with three thickness levels (4 mm, 10 mm and 20 mm) made of E-glass fibre, were used. Then 3D woven spacer fabrics were fabricated into their corresponding composites by hand lay-up technique using green epoxy resin. Characterization was done at both stages i.e. fabric and composite. Bending length and modulus of 3D woven spacer fabrics were decreased while the stiffness of the fabric was increased with increase in sample thickness. While in 3D woven spacer composites, 20 mm thick composite was more needle penetration resistant as compared to the 10 mm and 4 mm thick composites. Flexural and slow velocity impact performance of the 3D woven spacer composites was reduced with the increase of sample thickness. Flexural behaviour was better in weft direction as compared to the warp direction in all samples. Furthermore, 4 mm thick composite showed the highest value of energy absorbed and least deformation during the drop weight impact test.

This research was aimed at processing of metallic fiber hybrid spun yarns consisting of polyester/stainless steel and viscose/stainless steel staple fibers to achieve better electrical conductivity...

Titanium dioxide nanoparticles (TiO2-NPs) were prepared ultrasonically and simultaneously coated over cotton fabric activated with atmospheric pressure dielectric barrier (DBD) discharge. Titanium isopropoxide and extract of Aloe vera plant were used as a precursor and reducing agent, respectively, for the biosynthesis of TiO2-NPs. Cotton fabric was pre-treated with DBD plasma for different plasma exposure times. The effect of DBD plasma treatment on wettability and stability of TiO2-NPs on cotton fabric were studied. The obtained samples were investigated using Fourier transform infrared spectroscopy, UV–vis spectroscopy, scanning electron microscopy and X-ray diffraction to check the surface functionality, crystallite size and surface morphology. TiO2-NPs showed both spherical and triangular surface morphologies with dominating anatase phase and average crystallite size of 11.27 nm. The optimum condition for wettability was defined by using a water drop test method. Self-cleaning property of raw cotton, plasma-treated and plasma-TiO2-coated cotton fabric was evaluated by degrading methylene blue solution under daylight irradiation. The plasma-TiO2-coated fabric showed high self-cleaning efficiency due to firm bonding of nanoparticles on plasma-functionalized surface. The tensile strength of the fabric decreased slightly on plasma functionalization due to etching and pitting effects but increased after TiO2 coating of fabric.

Purpose The purpose of this paper is to investigate the effect of materials, three dimensional (3D) structure and number of fabric layers on ultraviolet protection factor (UPF), air permeability and thickness of fabrics. Design/methodology/approach Total 24 fabrics samples were developed using two 3D structures and two weft materials. In warp direction cotton (CT) yarn and in weft direction polypropylene (PP) and polyester (PET) were used. Air permeability, thickness and UPF testings were performed and relationship among fabric layers, air permeability, thickness and UPF was developed. Findings UPF and thickness of fabrics increases with number of fabric layers, whereas air permeability decreases with the increase in number of fabric layers. Furthermore, change of multilayer structure from angle interlock to orthogonal interlock having same base weave does not give significant effect on UPF. However, change of material from polyester (PET) to polypropylene (PP) has a dominant effect on UPF. Minimum of three layers of cotton/polyester fabric, without any aid of ultraviolet radiation (UV) resistant coating, are required to achieve good. Cotton/polyester fabrics are more appropriate for outdoor application due to their long-term resistance with sunlight exposure. Originality/value Long-term exposure to UV is detrimental. So, there is need of proper selection of material and fabric to achieve ultraviolet protection. 3D fabrics have yarns in X, Y as well as in Z directions which provide better ultraviolet protection as compared to two dimensional (2D) fabrics. In literature, mostly work was done on ultraviolet protection of 2D fabrics and surface coating of fabrics. There is limited work found on UPF of 3D woven fabrics.

For structural design applications, through-thickness characteristics of reinforcement played a vital role, which is why 3D woven preforms are recommended for such applications. These characteristics are mainly dependent on the fiber and yarn positioning in reinforcement. Although research has been conducted for characterizing woven composites, special attention has not been made on weave pattern parameter which directly affects the mechanical performance of composites. In this research work, 3D orthogonal layer to layer and through thickness woven structures with different interlocking patterns have been thoroughly studied for their mechanical properties, thickness, air permeability and areal density. Natural fibers when used with biodegradable matrix find use in structural, as well as low to medium impact applications for automobiles. Jute yarn was used to produce four-layered 3D woven structures, as synthetic fibers will not give a biodegradable composite part. The focus of this study is to optimize weave pattern, which is robust in design, degradable preforms and easy to reproduce. The main objective of this research focused on the effectiveness of weaving patterns on physical and mechanical properties as well as to optimize the weave pattern for optimum performance. Grey relational analysis was used for the optimization of the robust weave pattern. The results showed that hybrid structures can be useful for improving the properties of the orthogonal layer to layer and through thickness woven structures. It was also noted that weft-way 3D woven structures can provide comparable mechanical properties with warp-way 3D woven structures.

Nowadays, the auxetic materials, auxetic reinforcement as well as auxetic composite are under the great attention of scientific research due to having excellent mechanical properties. In the current research work, the impact resistance of composite was improved by modifying the four layer through the thickness woven structure, that was used as reinforcement. A comparison was made between the standard four layer through the thickness and modified four layer through the thickness woven structure in terms of auxeticity and penetration. The modified four layer through the thickness woven structure showed auxetic behavior in both warp and weft direction having less penetration resistance as compared to standard sample. The four layer through the thickness non-auxetic woven structures and modified auxetic four layer thorough the thickness woven structures were used as reinforcements to develop composite for impact resistance comparison. The result showed that impact resistance of auxetic composite was 6...

Heating fabric is an advanced textile materialthat is extensively researched by the industrialists and thescientists alike. Ability to create highly flexible and drapeableheating fabrics has many applications in everyday life.This paper presents a study conducted on the comparisonof heatability of knitted fabric made of stainless steelyarn. The purpose of the study is to find a suitable materialfor protective clothing against cold environments. Inthe current research the ampacity of stainless steel yarn isobserved in order to prevent the overheating of the heatingfabrics. The behavior of the knitted structure is studiedfor different levels of supply voltage. Infrared temperaturesensing is used to measure the heat generated from the fabricsin order to measure the temperature of the fabrics withoutphysical contact. It is concluded that interlock structureis one of the most suited structures for knitted heating fabrics.As learnt through this research, fabrics made of stainlesssteel yarn are capable of producing a higher level ofheating compared to that of knitted fabric made using silvercoated polymeric yarn at the same supply voltage.

The paper investigates the effects of weave structure and fabric thread density on the comfort and mechanical properties of various test fabrics woven from polyester/cotton yarns. Three different weave structures, that is, 1/1 plain, 2/1 twill and 3/1 twill, and three different fabric densities were taken as input variables whereas air permeability, overall moisture management capacity, tensile strength and tear strength of fabrics were taken as response variables and a comparison is made of the effect of weave structure and fabric density on the response variables. The results of fabric samples were analysed in Minitab statistical software. The coefficients of determinations (R-sq values) of the regression equations show a good predictive ability of the developed statistical models. The findings of the study may be helpful in deciding appropriate manufacturing specifications of woven fabrics to attain specific comfort and mechanical properties.

This paper presents the results of research work carried out to investigate the heating properties of nylon knitted fabric impregnated with a polymerised solution of polypyrrole. The inspection of the molecular polypyrrole electro-conductive pathways responsible for the heating effect of the knitted fabric was investigated using a scanning electron microscope. Further to this, the heat generated by the polypyrrole impregnated fabric was observed under varying power supply terminal separation distances in order to understand the relationship between the length of the polypyrrole electro-conductive fabric and the level of heat generated. The sample with the lowest terminal separation distance i.e. 5 × 1 cm2 produced more localized heat and reached a temperature level of 114℃ in less than three minutes. Additionally a thermo-mechanical characterisation of this knitted heating material was carried out against varying levels of strain and compression. The maximum stress and ultimate strain values of both treated and untreated samples were found to be similar. However, it was observed that the extensibility of the samples affected the generation of heat. The suitability of knitted fabric impregnated with polymerised polypyrrole heating elements for in-car applications where the heating elements may be next to skin was also discussed. The investigation concluded that polypyrrole heating fabric is suitable for next-to-body heating applications which can be engineered by controlling the optimum electrical pathways provided by the network of polypyrrole molecular chains together with the correct power supply levels to work under a defined fabric strain range. The purpose of the current research is to provide a new material that could help to develop heating fabrics with improved textile properties.

This study uses finite element analysis (FEA) numerical tool to determine the Poisson's ratio of different three‐dimensional (3D) woven structures. The simulation results reveal a coupled auxetic and bending behavior when a tensile force is applied. This study will help to choose the best 3D structure as reinforcement for ballistic grade impact applications in the area of wearable protection.

This paper presents a study conducted on the thermo-mechanical properties of knitted structures, the methods of manufacture, effect of contact pressure at the structural binding points, on the degree of heating. The test results also present the level of heating produced as a function of the separation between the supply terminals. The study further investigates the rate of heating and cooling of the knitted structures. The work also presents the decay of heating properties of the yarn due to overheating. Thermal images were taken to study the heat distribution over the surface of the knitted fabric. A tensile tester having constant rate of extension was used to stretch the fabric. The behavior of temperature profile of stretched fabric was observed. A comparison of heat generation by plain, rib and interlock structures was studied. It was observed from the series of experiments that there is a minimum threshold force of contact at binding points of a knitted structure is required to pass the electricity. Once this force is achieved, stretching the fabric does not affect the amount of heat produced.

Surgical gowns are the shielding cloths worn by the surgical team throughout a surgery to save them from bloodpathogens of the patient being operated, and to avoid bacterial infections. Barrier effectiveness of a fabric depends uponthe liquid penetration resistance and pathogen resistance of the fabric. The objective of this study was to analyze theeffect of different weave structures and fabric thread densities on the barrier effectiveness of the woven surgical gowns.Twelve fabric samples were produced using three different weave structures, i.e. 1/1 plain, 2/2 z-twill, and 3/3 z-twill,and four different fabric constructions and then completed with a water repellent finish. Water repellency spray test andair permeability test were conducted on each of the 12 woven samples. The results of fabric samples were analyzed inMinitab statistical software. The coefficients of determinations (R2 values) of the regression equations show goodprediction ability of the developed statistical models. The findings of the study may be helpful in deciding appropriatemanufacturing specifications of surgical gowns to attain maximum barrier effectiveness.

Respiratory and heart failure are conditions that can occur with little warning and may also be difficult to predict. Therefore continuous monitoring of these bio-signals is advantageous for ensuring human health. The safety belt is mainly designed to secure the occupant of the vehicle in the event of an accident. In the current research a prototype of safety belt is developed, which is used to achieve the respiratory and heart signal, under laboratory conditions. The current safety belt is constructed using the copper ink based peizo-resistive material, which works on the principle of pressure exerted on the sensor due to the expansion of the thorax/abdomen area of the body for respiration and due to the principle of ballistocardiography for heart signal sensing. The research explains the process of manufacturing the safety belt, preparation of cardio-respiratory sensor and integration of these sensors into the safety belt.