Fast response photochromic textiles from hybrid silica surface coating

In this study, a hybrid silica sol-gel embedded with a photochromic dye has been applied to wool fabric to form a photochromic coating. The treated wool fabrics showed very quick photochromic response. Five different silanes have been used as the silica precursor, and the resultant coating showed slight differences in photochromic performance, fabric washing fastness, and surface hydrophilicity. However, the silica type had a considerable influence on fabric handle property. The silica matrix from the silane containing a long alkyl chain had a very little influence on the fabric handle and better photochromic performance than those from other different silane precursors.

Novel conducting polymer films and coated textiles

This research developed non-hazardous methods for coating wool with conductive polymers for thermal and anti-static clothing. Conductive polymers are black in colour, thus the synthesis of new conductive polymers was required to produce coloured or fluorescent conductive textile. Cross-linked conductive polymers were also synthesised to increase their durability.

Improving nonwoven web quality with a new web scanning device

This thesis presents a novel web scanning device with high processing speed and optical sensitivity and a study of the interrelationships between dimensional parameters and functional properties of nonwovens using such a web scanning device.

Photochromic textiles from hybrid silica coating with improved photostability

Photochromic surface coating on textiles may create new fashion opportunities. It also enhances the ultraviolet (UV) protection ability of the coated products. In this study, a spirooxazine dye and a silane that bears a long alkyl chain have been used to produce hybrid photochromic silica coatings on wool fabrics. Four stabilisers are added separately to the photochromic silica coatings to examine their influence on photostability and photochromic behaviour. It is found that the addition of UV stabilisers slightly reduces the photochromic response speed and photochromic absorption. However, the addition of UV stabilisers to the photochromic coating considerably improves the photochromic lifetime. Among the four UV stabilisers studied, the quencher results in the best improvement to photostability with the lowest reduction in photochromic absorption.

An investigation of polypyrrole coated conductive textiles: this research aimed at clarifying some issues occurred in the research project on coloured conductive textiles

Coloured conducting textiles have shown a wide range of potential applications in heating fabrics, electromagnetic wave absorption, and wearable optoelectronic devices. This research aimed at clarifying some issues occurred in the research project on coloured conductive textiles. The investigation firstly clarified a possible chemical reaction that took place between a commercial dispersing dye (Terasil Red G) and the conducting polymer polypyrrole, through chemical separation, structural identification and spectrum characterisations. Then, a series of acidic dyes were introduced into polypyrrole matrix during the vapour coating of conducting polymer on the wool fabrics. Colour and thermal stability studies were conducted. Finally, the polypyrrole nanoparticles (particle size several~200nm) were prepared by a microemulsion polymerisation technique. An acid dye was used as the dopant to re-dope the nanoparticles. The effect of the acidic dye on the optical absorption of nanoparticles was studied. Applying the conducting nanoparticles on wool fabrics may open an alternative path to achieve the coloured conducting textiles.

Methods of coating textiles with soluble conducting polymers

Soluble conducting alkyl polypyrrole polymers have been applied by either chemical polymerization of the 3-alkyl monomers or direct application of polymer emulsion to the surface. Solution, vapor and spray polymerization methods of coating poly(3-alkylpyrroles) to the surface of woven wool fabrics are explored. Conductive textile samples have also been prepared by applying emulsions of soluble prepolymerized 3-alkylpyrrole to the fabric surface. Direct applications of a conductive paint to the textile surface eliminate the exposure of the substrate to damaging oxidizing agents which allow the coating of more sensitive and delicate substrates. All textiles produced are tested for abrasion resistance and conductivity. For alkyl polypyrrole coated fabrics, the optimum carbon chain lengths are between n=10 and n=14, which result in optimum values of conductivity and solubility. The darkness of the tone is inversely related to the surface resistivity of the resulting conductive fabric. Therefore, deep black coatings have low resistivity whereas light gray coatings on a white fabric surface have higher surface resistivity. Longer alkyl chains result in higher surface resistivity in fabrics. The conductive coating of poly(3-decanylpyrrole) on the textile surface has a better abrasion resistance compared to that of an unsubstituted polypyrrole coating.

Ultrafine wools: comfort and handle properties for next-to-skin knitwear and manufacturing performance

This study aimed to quantify the skin comfort and handle properties of a range of wool fabrics produced from ultrafine wool (13.7–15.1 µm) and in doing so determine if differences in fiber diameter and staple crimp frequency (5.3–7.1 crimps/cm) were important in these properties. The fabrics were evaluated using a range of subjective and objective measurement techniques, including the Wool ComfortMeter, the Wool HandleMeter and in wearer trials. This work indicated that single jersey fabrics made from ultrafine wool are approaching the limit of objective and subjective evaluation of next-to-skin comfort. The results from the Wool ComfortMeter, Wool HandleMeter and the wearer trial show that there were no significant effects that can be attributed to wool staple crimp (fiber curvature) in these ultrafine wool fabrics. The work also demonstrated a difference in the manufacturing response when knitted fabric made from wools of different fiber diameter (13.7–23.7 µm), and using yarns of the same count, resulted in a progressively higher fabric mass per unit area as mean fiber diameter was progressively reduced.

BFTB consumer serviceability test report.

Mimeographed.

Effect of cold plasma pre-treatment on photocatalytic activity of 3D fabric loaded with nano-photocatalysts: response surface methodology

In this study, the physico-chemical effects occasioned by the cold plasma discharge (CPD) on the photo-decolorization of Reactive Orange 16 (RO16) by 3D fabrics (spacer fabrics) loaded with ZnO:TiO2 nano-photocatalysts (nphs) were optimized via response surface methodology (RSM). CPD was employed to improve the surface characteristics of the spacer fabrics for nphs loading. Surface morphology and color variation were studied utilizing scanning electron microscopy (SEM) and CIE-Lab system, respectively. The effect of CPD on the wetting ability of the spacer fabrics was examined using dynamic adsorption measurement (DAM). Also, X-ray fluorescence (XRF) was utilized to investigate the durability of the nphs on the spacer fabrics. All the experiments were implemented in a Box-Behnken design (BBD) with three independent variables (CPD treatment time, dye concentration and irradiation time) in order to optimize the decolorization of RO16. The anticipated values of the decolorization efficiency were found to be in excellent agreement with the experimental values (R2 = 0.9996, Adjusted R2 = 0.9992). The kinetic analysis demonstrated that the photocatalytic decolorization followed the Langmuir-Hinshelwood kinetic model. In conclusion, this heterogeneous photocatalytic process is capable of decolorizing and mineralizing azoic reactive dye in textile wastewater. Moreover, the results confirmed that RSM based on the BBD was a suitable method to optimize the operating conditions of RO16 degradation.

Processing and quality of cashmere tops for ultra-fine wool worsted blend fabrics

This study has focussed on three main areas. First, an evaluation of the physical attributes of cashmere tops available to commercial spinners; second, the influence of processing variables on the efficiency of producing cashmere tops from raw Australian cashmere; and third, the influence of design of cashmere ultrafine wool blends on the fibre curvature of tops. Testing the physical attributes of cashmere tops from traditional and new sources of supply, was followed by statistical analyses based on factors of origin, processor and other determinants. The analyses demonstrated important processor effects and also that cashmere from different origins shows commercially important variations in fibre attributes. It was possible to efficiently produce Australian cashmere tops with Hauteur, tenacity, extension, softness and residual guard hairs quality attributes equivalent to those observed in the best cashmere tops. The blending of cashmere with wool resulted in a reduction of the mean fibre curvature of the blend compared with the unblended wool. The present work demonstrated that the fibre curvature properties of blended low crimp ultrafine wool tops were closer to the properties of pure cashmere tops than were tops made from blended standard high crimp ultrafine wool. The attributes of textiles made from the relatively rare Australian low curvature cashmere could enhance the marketability of both Australian cashmere and low curvature wool.

Predicting comfort properties of knitted fabrics by assessing yarns with the Wool ComfortMeter

This study examined the feasibility of assessing yarns with the Wool ComfortMeter (WCM) to predict the comfort properties of the corresponding single jersey-knitted fabrics. The optimum yarn arrangement to predict the comfort value of a corresponding control fabric was determined using nine wool and wool/nylon-blended yarns (mean fibre diameter range 16.5–24.9 μm) knitted into 34 different fabrics. Using a notched template, yarn winding frequencies of 1, 3, 6, 12, 25 and 50 parallel yarns were tested on the WCM. The best predictor of fabric WCM values was using 25 parallel yarns. Inclusion of knitting gauge and cover factor slightly improved predictions. This indicates that evaluation at the yarn stage would be a reliable predictor of knitted fabric comfort, and thus yarn testing would avoid the time and expense of fabric construction.

Predicting fabric prickle propensity by testing yarns on the Wool ComfortMeter

The Wool ComfortMeter is the first simple and fast objective tool in the world for assessing wool fabric prickle propensity. IWTO-DTM-66 for the measurement of fabrics using the WCM was accepted at the IWTO Cape Town Congress, South Africa in 2014. Since then, interest has been shown in the technology by yarn manufacturers and buyers for testing yarns before fabric is made, in order to obtain the prickle propensity of a fabric while still at yarn stage.Presentation of the yarn sample to the Wool ComfortMeter is critical. An YG381 yarn winder was selected for this project because it is a fast and reliable tool for sample preparation. The investigation into yarn winding density and tension showed that both the winding density and tension did not significantly affect the tested yarn WCM values. Therefore, a sample preparation protocol was established by using a winding density 19 loops/cm and a 20g tension plate on the YG381 winding machine.Further examination by complying with the preparation protocol showed that yarn Wool ComfortMeter value was the only significant predictor of its corresponding fabric Wool ComfortMeter value. Thus, liner and polynomial regression models were developed for predicting the fabric WCM prickle propensity. Based on the prediction performance, a linear model was recommended for the 1-ply yarns and polynomial model for the 2-ply yarns in this report. The prediction errors were approximately 66 for the 1-ply yarns and 14 for the 2-ply yarns.

Objective assessment of pilling of nonwoven fabrics using the two dimensional discrete wavelet transform

Fabric pilling is a serious problem for the apparel industry, causing an unsightly appearance and premature wear. Woolen products are particularly prone to pilling. Recently, a process for production of woolen nonwoven apparel fabrics has been commercialized in Australia, and may lead to new markets for Australian wool. However, the success of such nonwoven fabrics will partly rely on their propensity to pill. A key element in the control of fabric pilling is the evaluation of resistance to pilling by testing. Resistance to pilling is normally tested in the laboratory by processes that simulate accelerated wear, followed by a manual assessment of the degree of pilling by an expert based on a visual comparison of the sample to a set of test images. To bring more objectivity into the pilling rating process, a number of automated systems based on image analysis have been developed. The authors previously proposed a new method of image analysis based on the two-dimensional discrete wavelet transform to objectively measure the pilling intensity for woven fabrics. This paper presents preliminary work in extending this method to nonwoven fabrics.

Improvement of adhesion of conductive polypyrrole coating on wool and polyester fabrics using atmospheric plasma treatment

In this paper wool and polyester fabrics were pretreated with atmospheric plasma glow discharge (APGD) to improve the ability of the substrate to bond with anthraquinone-2-sulfonic acid doped conducting polypyrrole coating. A range of APGD gas mixtures and treatment times were investigated. APGD treated fabrics were tested for surface contact angle, wettability and surface energy change. Effect of the plasma treatment on the binding strength was analyzed by studying abrasion resistance, surface resistivity and reflectance. Investigations showed that treated fabrics exhibited better hydrophilicity and increased surface energy. Surface treatment by an APGD gas mixture of 95% helium/5% nitrogen yielded the best results with respect to coating uniformity, abrasion resistance and conductivity.

The dimensional and mechanical properties of wool/polyester fabrics made from vortex and ring-spun yarns

Fabric woven from wool/polyester (PES) Murata vortex spun (MVS) blend yarn is a commercially viable proposition particularly on the basis of advantageous wear-resistant properties, compared with fabric made from traditional worsted ring-spun yarn. However, in some early industrial trials with fabric made from 45/55-blend wool/PES MVS yarn, significantly greater relaxation shrinkage was found relative to comparable worsted ring-spun fabric. It was noted at the time that the amount of relaxation shrinkage in MVS fabric could be reduced to a large extent by using steamed MVS yarn.

In this study, the extent of variations in the dimensional and mechanical properties of fabric samples woven from a combination of steamed and unsteamed MVS yarn and equivalent worsted ring-spun yarn is examined. In general, greater hygral expansion and relaxation shrinkage were found in loom-state fabrics made from unsteamed MVS yarns, whereas the fabric made from steamed MVS and ring-spun yarns gave relatively low levels of relaxation shrinkage and hygral expansion. Permanent setting of fabrics, by pressure steaming, was found to be more effective than yarn pre-steaming in reducing relaxation shrinkage levels of fabrics made from unsteamed MVS yarn. After pressure steaming, all fabrics showed similar levels of relaxation shrinkage and hygral expansion.

Permanent setting of the fabrics, by pressure steaming, resulted in similar levels of relaxation shrinkage and hygral expansion, irrespective of the yarn production method; relaxation shrinkage fell to around 1% and hygral expansion increased by about 1%, relative to the loom-state samples. MVS fabrics were relatively heavier and fuller and had a firmer handle than the worsted ring-spun fabrics, reflecting the greater fabric weight, thickness and shear rigidity measured on these fabrics. These attributes are associated with different structures of the worsted ring-spun and MVS yarns used to make the fabrics.