Moisture management behaviors of high wicking fabrics composed of profiled Fibres

The effect of fibre cross-section shape, fibre content, yarn count, number of monofilaments, and loop density on moisture management properties of some knitted fabrics composed of profiled fibres has been investigated. The moisture management properties are assessed by moisture management tester in order to simulate the dynamic human body sweat transferring in different directions of clothing system. The indexes of the moisture management tester have been analyzed and interpreted regarding micro and macro equations of porosity, and horizontal and downward wicking. The results show that profiled cross-sectional fibres affect the moisture management and sweet transferring behaviors of functional knitted fabrics. Furthermore, accumulative one way transport capacity of fabrics is mainly dependent on both yarn (staples or filament) and fabric (loop density, knitting pattern and fabric thickness) structures

Moisture management behaviors of high wicking fabrics composed of profiled Fibres

318-324The effect of fibre cross-section shape, fibre content, yarn count, number of monofilaments, and loop density on moisture management properties of some knitted fabrics composed of profiled fibres has been investigated. The moisture management properties are assessed by moisture management tester in order to simulate the dynamic human body sweat transferring in different directions of clothing system. The indexes of the moisture management tester have been analyzed and interpreted regarding micro and macro equations of porosity, and horizontal and downward wicking. The results show that profiled cross-sectional fibres affect the moisture management and sweet transferring behaviors of functional knitted fabrics. Furthermore, accumulative one way transport capacity of fabrics is mainly dependent on both yarn (staples or filament) and fabric (loop density, knitting pattern and fabric thickness) structures

A new technique to tint the black dyed fibres in worsted spinning

250-256A new method has been developed for tinting of black dyed fibres of wool and polyester in worsted spinning system. The results of tinting process are evaluated by both visual and instrumentally<span style="mso-fareast-language:JA; mso-bidi-language:FA" lang="EN-GB">. The results show that the best option for tinting of black dyed fibres is the use of pigments in mixture with titanium dioxide, spinning oil and water. The tint solution is prepared by perfectly dissolving the components at the optimum values of 2.7% pigment, 2.4% titanium dioxide powder and 3.4% spinning oil in water at room temperature. It is observed that the proposed mixture can perfectly tint the black dyed fibres of wool and polyester without any permanent effect and stain on them<span style="mso-fareast-language: JA;mso-bidi-language:FA" lang="EN-GB">. T<span style="mso-bidi-language: FA" lang="EN-GB">he black dyed fibres could also be tinted in white colour with a solution of titanium dioxide without pigments. <span style="mso-fareast-language: JA;mso-bidi-language:FA" lang="EN-GB">The tinted fibres could be washed with water and detergents in finishing process easily and without any further stage. </span

Experimental verification of theoretical prediction of fiber to fiber contacts in electrospun multilayer nano-microfibrous assemblies: effect of fiber diameter and network porosity

Average number of fiber-to-fiber contacts in a fibrous structure is a prerequisite to investigate the mechanical, optical and transport properties of stochastic nanomicrofibrous networks. In this research work, based on theoretical analysis presented for the estimation of the number of contacts between fibers in electrospun random multilayer nanofibrous assembles, experimental verification for theoretical dependence of fiber diameter and network porosity on the fiber to fiber contacts has been provided. The analytical model formulated is compared with the existing theories to predict the average number of fiber contacts of nanofiber structures. The effect of fiber diameters and network porosities on average number of fiber contacts of nano-microfiber mats has been investigated. A comparison is also made between the experimental and theoretical number of inter-fiber contacts of multilayer electrospun random nanomicrofibrous networks. It has been found that both the fiber diameter and the network porosity have significant effects on the properties of fiber-to-fiber contacts.<br /

The effect of thermomechanical processing on the piezoelectric and electrical conductivity of PLA/2.5%MWCNT composite

The electrical properties of polymer materials, such as electrical conductivity and piezoelectricity, are significantly influenced by the ratio of amorphous to crystalline regions. Additionally, the alignment of added particles and formed crystallites is another factor that affects these properties. Conversely, a well-designed thermomechanical process can significantly impact the rate of change. This study investigates nanocomposite production with an optimal percentage of modified nanoparticles using a revamped electrospinning process and fully effective post-processing. Piezoelectric constant d33 of PLLA-2.5%CNT discussion was pioneered in this article. It was proved that the crystallinity percentage of nanocomposites can be improved by up to 70% by applying a suitable thermomechanical process and adding a suitable percentage of particles. The formation of the ordered phase, the creation of a special pattern for the movement of electrons, and the change in the conformation of the carbonyl group are the reasons for increasing the piezoelectric constant from 0.2 to 3 and increasing the electrical conductivity by 1000 orders of magnitude. Among other reasons, we can mention the alignment increment of polymer particles and crystallites and their way of texturizing in order to apply thermomechanical processing

The application of Cd Se/ZnS quantum dots and confocal laser scanning microscopy for three-dimensional imaging of nanfibrous structures

This paper reports a fast, accurate, and non-destructive three-dimensional imaging approach based on using quantum dots and confocal laser scanning microscopy to get three-dimensional images of internal pore structure of the nanofibrous materials. A practical method of making the fiber fluorescent using quantum dots was applied before three-dimensional imaging by confocal laser scanning microscopy. Fibrous scaffolds with different porosity parameters produced by electrospinning and their three-dimensional pore structure was evaluated by this approach. Furthermore, the introduced approach can be used to measure the pore interconnectivity of the scaffold<br /

Sandwich-type double-layer piezoelectric nanogenerators based on one- and two-dimensional ZnO nanostructures with improved output performance

Abstract Piezoelectric nanogenerators (PENGs) have attracted great interest owing to their broad range application in environmental mechanical energy harvesting to power small electronic devices. In this study, novel flexible and high-performance double-layer sandwich-type PENGs based on one-dimensional (1-D) and two-dimensional (2-D) zinc oxide (ZnO) nanostructures and Ni foam as the middle layer have been developed. The morphology and structure of 1- and 2-D ZnO nanostructures have been studied by scanning electron microscopy (SEM) and X-ray diffraction (XRD). To investigate the effect of structural design on the piezoelectric performance, single-layer PENGs were also fabricated. The piezoelectric output of all prepared PENGs were evaluated under different human impacts at various forces and frequencies. The double-layer designed PENGs showed a two times larger voltage output compared to the single-layer PENGs, and the use of Ni foam as middle-layer and of 2-D ZnO nanosheets (compared to 1-D nanorods) was also found to increase the performance of the designed PENGs. The working mechanism of the prepared PENGs is also discussed. The design of nanogenerators as double-layer sandwich structures instead of two integrated single-layer devices reduces the overall preparation time and processing steps and enhances their output performance, thus opening the gate for widening their practical applications

Synthesis of mesoporous functional hematite nanofibrous photoanodes by electrospinning

Iron(III) oxide (hematite, Fe2O3) nanofibers, as visible light-induced photoanode for water oxidation reaction of a water splitting process, were fabricated through electrospinning method followed by calcination treatment. The prepared samples were characterized with scanning electron microscopy, and three-electrode galvanostat/potentiostat for evaluating their photoelectrochemical (PEC) properties. The diameter of the as-spun fibers is about 300nm, and calcinated fibers have diameter less than 110nm with mesoporous structure. Optimized multilayered electrospun -Fe2O3 nanostructure mats showed photocurrent density of 0.53mA/cm(2) under dark and visible illumination conditions at voltage 1.23V and constant intensity (900mW/cm(2)). This photovoltaic performance of nanostructure mats makes it suitable choice for using in the PEC water splitting application as an efficient photoanode. This method, if combined with appropriate flexible conductive substrate, has the potential for producing flexible hematite solar fuel generators. Copyright (c) 2015 John Wiley & Sons, Ltd