Thermophysiological Comfort Research Articles

High‐Speed Spun PET Nanocomposites for Smart Multifunctional Approaches

ABSTRACTHigh‐speed spinning at 3000 m/min with a remarkable potential for mass production was conducted to produce continuous fine‐multifilament nanocomposite yarns on a pilot plant scale. Nanocomposite fabrics were produced via a simultaneous draw‐texturing process followed by weft knitting. The fabric samples were examined in terms of thermophysiological comfort, tribological performance, and the resistance against structural degradation under ultraviolet (UV) irradiation. The abrasion resistance was improved by enhancement of rupture work while decreasing the crystallinity. Improvement of more than 200% was recorded in fabric abrasion resistance upon using a sample containing the maximum content of nanoparticles (NPs). A remarkable improvement in resistance was recorded against structural degradation under UV irradiation for the UV‐irradiated polyethylene terephetalate (PET) nanocomposites as compared to UV‐irradiated monocomponent PET. The study of the effect of UV irradiation confirmed our recent finding about a UV‐induced solid‐state interaction mechanism in the case of PET nanocomposites as well as polypropylene (PP) nanocomposites. Optimal comfortable characteristic was achieved upon using 5 wt% nanosilver masterbatch. At low environment temperatures, this sample has lower vapor permeability than monocomponent PET fabrics. By raising the temperature, the rate of improving the vapor permeability for the composite fabrics became markedly more than that of monocomponent fabrics. It is of great interest that these desirable changes in permeability can be achieved in the range of common environment temperatures (i.e. 15–35°C), which exactly meet the body requirements. Consequently, nanocomposite fabrics can smartly adapt the permeability requirements for the human body by changing the environment temperatures.

The change of water vapour resistance of materials used for the clothing production during exploitation

The aim of the paper was to test the changes of thermo-physiological properties of fabrics occurring during the clothing maintenance, i.e. washing. Hot plate measurements were used. The test results were not observed separately but in terms of interrelatedness of the material properties. The obtained results show that certain yarn properties have a substantial impact on the change of water vapour resistance of the fabrics (Ret), and were used to establish a mathematical model for predicting thermophysiological comfort of woven structures while being used, i.e. cared for. The conducted research enabled the description, classification and definition of the elements of relatedness of fabric parameters with thermophysiological properties of a cloting item, based on which the comfort parameters of similar fabrics, as well as the usage properties of the products made of them can be predicted.

Effects of Clothing Material Dyed with Astringent Persimmon Extract upon Exercise-Induced Thermal Strain and Sensory Responses in a Warm Environment

This study investigated the effects of persimmon-dyed clothing materials upon thermophysiological responses and subjective comfort sensations during exercise and rest in a warm environment. Six healthy, untrained women participated in two separate testing sessions, with cotton materials dyed with astringent persimmon extract (DC) and undyed cotton materials (UDC). The physical characteristics associated with heat and moisture transfer were improved in DC; also, stiffness, anti-drapery stiffness and crispness in the primary hand values were higher in DC. The experimental protocol consisted of a 10-min rest, 15-min exercise on a treadmill (at ) and 25-min recovery at and . The results were as follows: When wearing DC rather than UDC, mean body temperature, heart rate, heat storage and body mass loss were significantly lower during the whole experimental period. Clothing microclimate temperature showed different profiles between the two clothing materials, being lower with DC than UDC during the first half of exercise and the second half of recovery. Clothing microclimate humidity was significantly lower with DC than UDC during the whole experimental period. When wearing UDC, subjects felt significantly warmer and less comfortable during exercise, and sensed greater humidity during exercise and recovery. These results suggest that eco-friendly clothing materials dyed with astringent persimmon extract can reduce exercise-induced heat load and improve subjective sensations when exercising and resting in a warm environment, due to greater heat dissipation from the body to the outside environment compared with undyed clothing materials.

Moisture Management Behaviour of Knitted Fabric from Structurally Modified Ring and Vortex Spun Yarn

The acceptability of a new product is decided by its performance, level of improvement in quality and economy of production. The basic aim of generating micro pores in a textile structure is to provide better thermo-physiological comfort by enhancing the breathability and hence improving moisture management behaviour. In the present study, an attempt has been made to create a relatively more open structure through removal of a component. A comparative assessment with a homogeneous and parent yarn was also made. Yarns of two linear densities, each from ring and vortex spinning systems were produced using 100 % polyester and 80:20 polyester/cotton blend. The modified yarn was produced by removing a component, viz; cotton, by treatment with sulphuric acid from the blended yarn. The knitted fabric from modified yarn was found to show significant improvement in air permeability, water vapour permeability and total absorbency while the wicking characteristic was found to decline.

Permeability and impact properties of warp-knitted spacer fabrics for protective application

An experimental investigation was carried out to study the effect of interlining material on the comfort and dynamic deformation characteristics of body armour. Suitable plies of interlining materials were selected based on the fabric comfort properties and the impact resistance specified for ballistic application. Kevlar woven fabric was used to block the projectile, and the spacer fabric was used as an interlining material to ensure wearing comfort and for imparting impact resistance. The yarn denier of the middle and bottom layers of the spacer fabrics was maintained constant, and three different deniers were used for the face layer. Three different plies of spacer fabrics were analysed by means of thermophysiological comfort properties to select the suitable interlining material for body armour. The experimental results confirm that the number of plies of spacer fabrics has significant influence on the ballistic armour characteristics than the face layer denier as proved by two-way ANOVA. The substantiated spacer fabric was used as an interlining material, and the depth and area of deformation were analysed. The research findings demonstrated that the three-plied warp-knitted polyester spacer fabric produced better results than single- and five-plied spacer fabrics. One-way ANOVA and Turkey’s HSD also confirmed the influence and interaction of different plies of spacer fabrics.

Effect of woven fabric structure on the air permeability and moisture management properties

In this study, six different woven samples were produced on air jet loom with two different weave designs (i.e. 3/1 twill and 1/1 plain), three different picking sequences (i.e. single pick insertion (SPI), double pick insertion (DPI) and three pick insertion (3PI)). All the woven samples were singed, desized, bleached and finished together at industrial scale, as a single lot. The effect of these factors on the wetting, wicking and air permeability (AP) of the fabric samples was analysed. It was revealed that the fabric weave design and picking sequence has statistically significant effect on fabric wetting time, water spreading speed and AP of the fabric. It was found that fabrics woven in twill weave design and with simultaneous 3PI give significantly better AP, shorter wetting time and better water spreading rate as compared to plain woven fabrics and those with double or SPI. It could be concluded that the thermophysiological comfort of woven fabrics may be significantly improved simply by selecting a suitable weave design and picking sequence.

Evaluation and improvement of thermo-physiological comfort properties of firefighters’ protective clothing containing super absorbent materials

In this research, super absorbent materials were incorporated into the internal layer of the firefighters’ protective clothing with the aim of increasing absorption of sweat to improve the thermo-physiological comfort properties. The performance properties were evaluated following the standard test methods (ISO 6942:2002 and ISO 9151: 1995(E)) and the thermo-physiological comfort-related properties were evaluated by measuring the transport properties such as air permeability, water sorption and evaporation, thermal resistance and water vapour resistance of the fabric assemblies with super absorbent materials. The results indicated that it is possible to improve the comfort properties of the protective clothing by the incorporation of super absorbent materials into the internal layer. The use of super absorbent materials is likely to help in the absorption of sweat in higher amount and keeping the skin and internal microclimate dry, which in turn improves the comfort level. The performance properties of all the combinations satisfied the requirements for firefighter’s clothing as mentioned in AS/NZS 4967-2009.

Efficiency of Nano QACs antibacterial treated garments

Growth of bacteria on textiles possesses a range of unwanted negative effects; initially irritation and up to reach eczema, these are concerning the wearer, particularly, if grown bacteria are into socks or underwear; also clothes can generate unpleasant odour, stains and discoloration in the fabric, as well as reduction in fabric strength and subsequently contamination. In the medical field, incorporating bacteria within nursing gowns can be fatal. Aim of this paper, is to assess the functional efficiency of nano-quaternary ammonium compounds (QACs) treated garments; including woven nursing gowns, knitted under-wears and socks. Methodology was undertaken using a number of nine different clothing materials; both woven and knitted garments, with fibre content of 100% cotton, PES/cotton and 100%PES. All of which were treated using nano-QACs antibacterial substance. Both treated and untreated garments were examined using a number of test methods; first, the agar diffusion plate, second, thermo-physiological comfort properties of wettability and heat-loss, finally, spray test was done evaluating stain resistance of nursing gowns.

Thermophysiological comfort properties of selected knitted fabrics and design of T-shirts

Thermal comfort is one of the most important components of comfort which shows physiological, psychological, and physical harmony between human body and environment. The heat and moisture transfer capacity of fabric from skin to environment affects the thermal comfort of garments. The transfer capacity depends on the characteristic features of raw materials and fabric structural properties. In this study, it is aimed to determine the advantages of knitted fabric types, taking into account the environmental condition and activity level by measuring the thermal comfort properties such as air permeability, wicking, moisture management, thermal and water vapor resistances. Two knitted structures composed of tuck and float combinations and six raw materials were chosen for the fabrics produced. According to the measurement results, the polyester and cotton/Coolmax fabrics with float stitches have had good liquid moisture transport properties. Besides, high air permeability and low water vapor resistance have been obtained in viscose and Tencel LF fabrics with tuck stitches. On the basis of the results obtained in this investigation, and taking into consideration thermal behavior of human body, four women’s and five men’s T-shirts are designed. These T-shirt designs may be helpful for further approaches on the optimization of thermal comfort for sports activities in hot environment.

Therapy gloves for patients with rheumatoid arthritis: a review.

Rheumatoid arthritis is a chronic inflammatory disease that causes pain, joint stiffness and swelling leading to impaired hand function and difficulty with daily activities. Wearing therapy gloves has been recommended by occupational therapists as one of the alternative treatment methods for rheumatoid arthritis. This study aims to review the available literature on the effects of wearing therapy gloves on patients' hand function and symptoms as well as to discuss the attributes of gloves that might influence the glove performance. An electronic databases search of MEDLINE, Physiotherapy Evidence Database, Occupational Therapy Systematic Evaluation of Evidence, Wiley Online Library, ScienceDirect and Cochrane Central Register of Controlled Trial was performed. Eight articles met the inclusion criteria, and covered seven clinical trials and one case study. Seven outcome measures were identified from the included studies and were then classified into two categories: hand function and hand symptoms. The hand symptoms such as pain, stiffness and swelling improve substantially when the therapy gloves are used. However, marginal or no improvement in hand function (with the exception of grip strength) linked to the use of therapy gloves is being reported. Further research is needed to quantify the effectiveness of therapy gloves, especially in improvement of hand function and in patients' interest in wearing therapy gloves. Furthermore, future studies should include parameters which might influence therapy gloves' performance, such as duration of trials, interface pressure generated by the gloves on the underlying skin and tissue, glove fit and construction, as well as thermophysiological comfort.

Improving Thermo-Physiological Comfort of Polyester/Cotton Knits by Caustic and Cellulases Treatments

Abstract Cotton is one of the most commonly used fibres for making knitwear. Some of the limitations of pure cotton knits include their tendency to shrink, relatively limited durability, and poor wash and wear properties. In order to overcome these limitations knitwear are also produced from polyester and cotton blends, however, at the cost of reduction in comfort properties. The objective of this study was to improve the thermo-physiological comfort properties of knits made from polyester/cotton (P/C) blends through simple chemical and biological treatments. The specimens of P/C knits were subjected to treatments with caustic soda solutions and the cellulase enzymes. It was found that the air permeability and perspiration management properties of P/C knits can be significantly improved by appropriate caustic treatment. However, the biological treatment with cellulase enzymes is comparatively less effective in making any improvement in the thermo-physiological comfort properties of P/C knits.

Design of functional knitted fabrics for medical corsets with high clothing comfort characteristics

This study aims to achieve high comfort characteristics in medical corsets. For this aim, initially the expectations of users were determined by a survey and special yarns have been selected according to the survey responses. Then, different corset fabrics have been designed in a functional structure. Later, the most important body movement (stretchability), sensorial (bending rigidity) and thermophysiological comfort (air permeability, water vapour permeability, and thermal resistance) properties of these fabrics were tested and evaluated statistically. The results revealed that high levels of clothing comfort and performance properties can be established by different yarn types and fabric compositions and this will lead to achieve a successful medical therapy.

Thermo-physiological Comfort Properties of Polyester and Polyester/Acrylic blended Synthetic Fabrics treated with Herbal Finishes

Thermo-physiological comfort in clothing mainly lies in moisture management, which often refers to the transport of both moisture vapor and liquid away from the body. Moisture management of fabrics is chiefly influenced by the thermal properties of those fabrics. In spite of the convincing properties that synthetic fabrics have, they are not much preferred because of their hydrophobic nature which provides less comfort to the wearer compared to the natural fabrics like cotton, wool, and silk. Previous studies report that the herbal finishes, which are eco-friendly in nature, improve the anti-microbial and other medicinal properties but very little or no work has been carried out on the comfort aspect of these fabrics. This work reports a study of the influence of two ecofriendly herbal finishes, Neem and Bermuda grass, on the thermo-physiological comfort properties of synthetic fabrics used in clothing. The herbal finishes were applied on to 100% Polyester and 50/50 Polyester/Acrylic blended fabrics. Prior to the application of finishes, the fabrics were given a pretreatment to achieve a better penetration and durability of the finishes. The finished fabrics were tested for the thermo-physiological comfort properties of Wicking, Water vapor permeability, and Thermal conductivity and the results were analyzed. It was revealed that both the Neem and Bermuda grass natural finishes considerably improved the moisture related properties and moderately reduced the thermal conductivity characteristics of the above synthetic fabrics. Durability to washing was also tested and discussed.

Effect of finishing treatments on heat resistance of one- and two-layered fabrics

A series of cotton knitted fabrics was produced and finished according to three different recipes in order to compare the changes of their heat resistances. The heat resistance was measured using the sweating guarded hotplate. Measurements were carried out on one layer of produced knitted fabrics, as well as on two layers of fabrics. The results indicated significant influence of all carried finishing treatments to the decrease of heat resistance of knitted fabrics. It was shown that the high influence of finishing treatment to the total heat transfer trough fabric remains if the fabric is worn with additional knitted fabric layer. The presented results and performed statistical analysis indicated significant effect of finishing treatments to the changes of fabric parameters and furthermore to the changes of heat resistance what directly affects the total thermophysiological comfort of knitwear.

Statistical models for predicting the thermal resistance of polyester/cotton blended interlock knitted fabrics

Thermal resistance is one of the key aspects of thermo-physiological comfort of knitted clothes. The aim of this study was to develop statistical models for predicting the thermal resistance of polyester/cotton blended interlock knitted fabrics. Fabric samples were knitted at three different tightness levels, with yarns of three different linear densities each with three different polyester/cotton blend ratios. Based on thermal resistance results of the knitted samples, three different statistical models were developed comprising different input variables as predictors. The validation results showed that the thermal resistance of polyester/cotton interlock fabrics could be predicted using the developed statistical models with an average percentage error of 4–8%. It could be concluded from the sensitivity analysis that the most influential factor affecting the thermal resistance was fabric stitch length, followed by yarn specific heat and fabric areal density.

Moisture management properties of plated knit structures with varying fiber types

Thermo-physiological comfort of clothing designed for next-to-skin applications is influenced by the clothing’s ability to manage heat and moisture transfer thereby maintaining dry skin microclimate. Plated knit structures designed and engineered with correct selection of fiber and yarn constituents in the distinct bottom (exposed to environment) and top (next to sin) layers can serve well for next-to-skin applications. In this study, plated fabrics with altering hydrophilic and hydrophobic fibers in top and bottom layers and different types of hydrophobic fibers in top layers have been compared for the moisture management properties. Results show that fabrics knitted with hydrophobic fibers (polypropylene, polyester) in top layers seem suitable for next-to-skin applications as they were classified as moisture management fabrics owing to high values of accumulative one-way transport index and bottom spreading speed. Though both fabrics can be recommended for next-to-skin applications, however, polypropylene on account of superior moisture management properties in the top layer would be more effective in providing dry feel next to skin and hence, seems to be a preferred choice over polyester for such applications. Fabric knitted with nylon in top layer was classified as water penetration fabric due to poor liquid transfer properties. Fabrics knitted with cotton in top layer irrespective of the hydrophobic fiber in bottom layer were poor in moisture management properties. Univariate analysis of variance with a confidence level of 95% showed the results to be statistically significant. Pearson correlation coefficient was obtained for all the moisture management indices by bivariate correlation procedure to determine strength and direction of association between the different moisture management indices. Most of the indices were found to be significantly correlated also, OWTC and OMMC were found to be positively and linearly related to each other.

Thermophysiological comfort properties of different knitted fabrics used in cycling clothes

In this paper, we measured the thermal and moisture management properties of six different types of polyester knitted fabrics that are used in the production of summer cycling clothes. The test samples were selected from the most commonly used fabric structures according to the results of a survey on a cycling team in Bursa. The fabrics were compared to determine which fabrics were more convenient for cyclists. Thus, we carried out objective fabric tests to determine the thermal resistance, water vapor resistance, air permeability and moisture management properties. Good moisture comfort, low water vapor resistance and good moisture management properties were preferred, especially in summer clothes. In the final evaluations of the fabrics, it was found that Type 6 Warp knitted raschel fabric was more convenient for summer cycling clothing because of its good air permeability, low thermal resistance, low water vapor resistance and good moisture management properties.

A model of heat and moisture transfer through clothing integrated with the UC Berkeley comfort model

A detailed model of heat and moisture transfer through clothing has been developed and implemented in the multi-segment UC Berkeley Thermophysiological Comfort model (BTCM). Equations are presented for two paths of heat and moisture transfer, between naked skin and environment, and clothed skin and environment. Transient behavior due to absorption and desorption by clothing is included. Segment-specific values for clothing insulation, vapor resistance, and the effects of air movement and walking are estimated from various sources. The new model is shown to simulate results from empirical studies with good accuracy. Parametric simulations are done to evaluate the physiological and comfort influences of the airspeed correction equations, and the heat transfer effects of different clothing levels at different temperatures. The results quantify the substantial air velocity and air temperature impacts on thermal physiology and thermal comfort. It can be seen that the new model is useful for studying heat and moisture transfer through clothing, and evaluating thermal comfort in transient environments.

Processing and Characterisation of the Copper Treated Polylactic Acid and Cotton Fabrics: Thermophysiological Comfort Properties

The main objective of this study is to develop a novel copper treatment method and characterise the effect of treatment on the thermophysiological comfort properties of the treated fabrics. It is also aimed to analyse and evaluate the thermophysiological properties of the PLA fabrics. The study was conducted by using polylactic acid (PLA), cotton and their blend yarns. The knitted fabrics, single pique, were made from these yarns by using weft knitting machine. The fabrics were treated with two copper solution concentrations (5 % and 10 %) at 20 minutes ultrasonic energy. The results show that the treatment has a critical effect on the tested fabrics in terms of thermal conductivity, thermal resistance, thermal absorbtivity, water vapour permeability, and heat loss. The results also clearly demonstrated that the PLA fabric was successfully treated with the copper solution, and the coated fabrics showed significant change as compared to their untreated counterparts in terms of tested parameters. DOI: http://dx.doi.org/10.5755/j01.ms.20.1.1853

Thermophysiological Comfort Analysis of Aerogel Nanoparticle Incorporated Fabric for Fire Fighter’s Protective Clothing

The paper discusses the thermophysiological comfort of a newly developed fabric potentially for firefighter's protective clothing. The fabrics were developed by incorporating super hydrophobic silica aerogel nanoparticles in 65/35 wool-Aramid blended fabric. Then the theromophysiological comfort was analyzed by determining air, moisture and heat transfer performance. It has been found that only 2% coating of aerogel nanoparticle increases thermal resistance by up to 68.64% and can reduce air permeability by up to 45.46% whereas 4% aerogel coating can reduce 61.76% air permeability. Moisture management properties of the aerogel coated fabric have also been investigated and discussed in details. In brief, it can be said that the thickener that was used for the coating, has a positive impact on moisture transportation and overall moisture management property of the fabric. Again aerogel coated next-to-skin layer and aerogel coated outer layer acted differently on the same fabric. It was observed that, the coated fabric acts as more likely as a moisture management fabric when the coating was applied on next-to-skin surface.