Positron annihilation lifetime spectroscopy of mechanically milled protein fibre powders and their free volume aspects

The present study reports the fabrication of ultra-fine powders from animal protein fibres such as cashmere guard hair, merino wool and eri silk along with their free volume aspects. The respectively mechanically cleaned, scoured and degummed cashmere guard hair, wool and silk fibres were converted into dry powders by a process sequence: Chopping, Attritor Milling, and Spray Drying. The fabricated protein fibre powders were characterised by scanning electron microscope, particle size distribution and positron annihilation lifetime spectroscopy (PALS). The PALS results indicated that the average free volume size in protein fibres increased on their wet mechanical milling with a decrease in the corresponding intensities leading to a resultant decrease in their fractional free volumes.

Tri-component bio-composite materials prepared using an eco-friendly processing route

We report on the blending of three natural polymers, raw cotton, silk and wool, using ionic liquids as the dissolving media. We find that with increased content of wool and silk the thermal degradation temperature of the new bio films increases. This is due to an increase in the hydrogen bond network between the blended polymers. We also investigated the role of the coagulating solvent by coagulating the bio films using water, methanol or isopropanol. Again, we find the coagulating solvent impacts the final properties of the bio films with water shown to coagulated films with the best material properties.

Variation in the softness and fibre curvature of cashmere, alpaca, mohair and other rare animal fibres

Softness of apparel textiles is a major attribute sought by consumers. There is surprisingly little objective information on the softness properties of rare animal fibres, particularly cashmere, alpaca and mohair. Samples of these and other rare animal fibres from different origins of production and processors were objectively measured for fibre diameter, fibre curvature (FC, crimp) and resistance to compression (softness). While there were curvilinear responses of resistance to compression to FC and to mean fibre diameter, FC accounted for much more of the variance in resistance to compression. Fibre type was an important determinant of resistance to compression. The softest fibres were alpaca, mohair and cashgora and all of the fibres measured were softer than most Merino wool. Quivet, llama, camel, guanaco, vicuña, yak wool, bison wool, dehaired cow down and Angora rabbit were also differentiated from alpaca, mohair and cashmere. There were important differences in the softness and FC of cashmere from different origins with cashmere from newer origins of production (Australia, New Zealand and USA) having lower resistance to compression than cashmere from traditional sources of China and Iran. Cashmere from different origins was differentiated on the basis of resistance to compression, FC and fibre diameter. Cashgora was differentiated from cashmere by having a lower FC and lower resistance to compression. There were minority effects of colour and fibre diameter variation on resistance to compression of cashmere. The implications of these findings for the identification and use of softer raw materials are discussed.

Reinventing D'Jillong : current regeneration initiatives challenging the identity and place of Geelong

Australian regional city regeneration in Australia is increasingly becoming an important topic as they attempt to position themselves mid-way between larger discourses about capital cities and peri-urban landscapes. Historically these cities, like Newcastle, Wollongong and Geelong, have been marginalised in infrastructure and planning support systems, yet subject to erratic Commonwealth and State funded initiatives that have divested major specific-purpose complexes into their cities. Such has been as a consequence of of 'decentralisation' and 'regionalisation' political platforms, but also to address employment and voting needs. As an example, Geelong embraced contemporary industrialism, particularly automotive, and built on its port and wool export capacities. Politics, intransigence and lack of economic investment compounded the failure to create quality urban fabric and enable innovative planning. With this legacy, this regional city finds itself at the cusp of heavy industry disintegration, education and health sectorial growth, population increases aided by regional escapism, and a lethargic city centre. In attempting to redress these trends, Geelong is consciously attempting to re-image itself, regenerate key sections of its urban fabric, but also manage the regional escapism (sea change / tree change) phenomena. This paper critiques the larger context, and then uses three examples - "Vision 2" in the city centre, the Mega Port proposal, Fyansford Green and the Moolap salt marsh - as foils to reflect whether these initiatives are and can assist the facilitation of city structural change, economic renewal and enhanced urban design and place-making outcomes.

The relationship of the incidence of medullated fibres to the dimensional properties of mohair over the lifetime of Angora goats

In a range of animals, increasing mean fibre diameter (MFD) of fibre is associated with an increasing incidence of medullated fibres (Med). It would thus be expected that Med in mohair fleeces, from animals in a flock, would be related to the MFD of those fleeces. MFD of mohair is not the only dimensional attribute of fibres. Med in mohair is phenotypically and genetically related to the size of animals. This study examined how Med is related to dimensional properties of mohair over the lifetime of Angora goats and how the relationship varies with other lifetime factors. The relationship found is then examined to determine the extent that the relationship can be explained by variations in animal size of the goats. Measurements were made over 11 shearing periods on a population of Angora goats representing the current range and diversity of genetic origins in Australia, including South African, Texan and interbred admixtures of these and Australian sources. Records of breed, sire, dam, date of birth, dam age, birth weight, birth parity, weaning weight, live weight, fleece growth and fleece attributes were taken for castrated males (wethers). Animals’ fleece-free live weight (FFLwt, kg) were determined for each goat at shearing time by subtracting the greasy fleece weight from the live weight recorded immediately prior to shearing. The average of the FFLwt at the start of the period and the FFLwt at the end of the period was calculated. Two restricted maximum likelihood (REML) models were developed to relate Med to MFD, staple length (SL) and other lifetime factors. One model allowed FFLwt in the model and the other excluded FFLwt. With the exception of the 1.5 years shearing, Med strongly increased with increasing MFD whether or not adjustments were made for FFLwt measurements. In particular Med increased by 2.0% for each 1 μm increase in MFD, with no adjustment for FFLwt measurements, and increased by 1.5% for each 1 μm increase in MFD, with adjustment for FFLwt measurements. Within each shearing interval increasing average FFLwt was associated with increasing incidence of Med in a similar way to that which has been previously reported without including MFD in the model. There was no evidence that SL needed to be included in the models for Med. Mohair grown by the goats of Mixed genetic background grew mohair which had a higher incidence of Med at ages 2 and 2.5 years and the trend was apparent in other shearing periods. We can conclude that there is both a large response of Med to live weight and a large response to MFD, and that these responses are largely functionally separate. While the response to MFD is in accord with earlier work, there is an unrelated and unreported physiological mechanism that favours the production of Med in larger Angora goats. Clearly, larger Angora goats are biologically different compared with smaller animals from the same flock, in ways that are not purely related to the allometrics of size.

Effects of different nutritional regimens on the productivity of Australian Cashmere goats and the partitioning of nutrients between cashmere and hair growth

The influence of energy or protein supplementation or energy restriction on cashmere growth was studied in 35 highly productive cashmere wether goats. The goats were shorn on 3 December and randomly allocated to 3 levels of energy intake: M, goats fed to maintain liveweight; 0.8M, goats fed to lose 5 kg liveweight from December to April and then fed ad libitum; and >M, goats fed to gain liveweight. Nested within >M were ADLIB (goats offered feed ad libitum), and 1.25M and l.5M (goats fed M plus 25 or 50% of the difference in mean intake between M and ADLIB). The metabolisable energy requirement to maintain liveweight was 250 kJ kg-0.75 day-1 but to maintain body condition (l.25M) it was 3 12 kJ kg-0.75 day-1. Goats fed 0.8M had a mean intake of 0.68M and lost 26 g day-1 liveweight until April, but when fed ad libitum consumed 2.15M in June and grew rapidly in late autumn and winter at 93 g day-1. Goats fed ADLIB consumed 2.30M in February and gained 87 g day-1 from December to February, but intake declined to 1.61 M in June and they gained 20 g day-1 from April to June. Cashmere growth and fibre diameters of fleeces shorn on 17 June of goats fed >M (221g, 17.69 pm) were significantly greater (P< 0.02) than those of goats fed 0.8M (146 g, 16.67 ¦m), with levels of M-fed goats being intermediate. Within >M, there were no significant differences in cashmere growth. Protein supplementation within M (27 or 54 g day -1 formaldehyde- treated casein) resulted in 40% more wool growth in sheep (P<0.001), but no increase in cashmere or hair growth in goats. Goats fed ADLIB had significantly reduced cashmere yields (P < 0.05) and grew more hair (P<0.05) than did goats in other treatments. About 4 weeks after energy supplementation, fibre diameter of previously energy-deprived goats increased (P< 0.01). Midside patches indicated that energy-deprived goats, which lost liveweight, diverted nutrients preferentially to cashmere growth, while goats fed ADLIB partitioned nutrients towards hair growth. To maximise cashmere growth, supplementary energy should be supplied to avoid liveweight loss from December to April. Goats that had small (1-2 kg) liveweight gains and maintained body condition achieved near maximal levels of cashmere growth.

What happens during natural protein fibre dissolution in ionic liquids

Here, we monitor the dissolution of several natural protein fibres such as wool, human hair and silk, in various ionic liquids (ILs). The dissolution of protein-based materials using ILs is an emerging area exploring the production of new materials from waste products. Wool is a keratin fibre, which is extensively used in the textiles industry and as a result has considerable amounts of waste produced each year. Wool, along with human hair, has a unique morphology whereby the outer layer, the cuticle, is heavily cross linked with disulphide bonds, whereas silk does not have this outer layer. Here we show how ILs dissolve natural protein fibres and how the mechanism of dissolution is directly related to the structure and morphology of the wool fibre. © 2014 by the authors; licensee MDPI, Basel, Switzerland.

The value of visual fleece assessment in addition to objective measurements in identifying Angora goats of greater clean mohair production

Visual assessment of the fleece of Merino sheep is an accepted method to aid genetic improvement but there is little evidence to support the use of visual assessment for improving mohair production. This paper examines the extent that visual traits, including staple length, character (staple crimp), staple definition, tippiness, style and staple entanglement, are related to clean fleece weight in animals of similar live weight and mean fibre diameter (MFD) from the same flock. Measurements were made over 9 shearing periods on a population of castrated Angora males (wethers) goats representing the current range and diversity of genetic origins in Australia, including South African, Texan and interbred admixtures of these and Australian sources (these different genetic origins are defined as Breed in this work). Data on genetic origin, sire, dam, lifetime characteristics (date of birth, dam age, birth weight, birth parity (single or twin), weaning weight), live weight, fleece growth and visual fleece attributes were recorded. A restricted maximum likelihood (REML) model was developed to relate clean fleece weight with age, MFD, average fleece-free live weight, lifetime characteristics and visual fleece attributes. There were separate linear responses of clean fleece weight to MFD and staple length for each age group, a quadratic response to the square root of average fleece-free live weight, an effect of sire breed and linear responses to dam age, staple definition score and character. Depending on age at shearing, the increase in clean fleece weight was between about 50 and 80. g for each increase of 1. μm in MFD. At similar MFD, clean fleece weight was generally greater at summer shearings compared with winter shearings. There was a strong increase in clean fleece weight with average fleece-free live weight up to around 50. kg but little response in clean fleece weight for animals larger than 50. kg. There was some evidence of a smaller increase in clean fleece weight as the age of dam increased. There was an effect of Breed in the model but this effect disappeared when a random sire effect was included in the model. There was a positive response to staple length at some age groups but the response did not differ from zero in other age groups. This response varied from negligible to about 70. g per 1. cm increase in staple length. Clean fleece weight increased about 40. g per unit increase in staple definition score and increased about 30. g for every 4 units increase in the number of staple crimps. There was no evidence that clean fleece weight was affected by staple style, staple tip score or staple entanglement score or lifetime factors such as birth weight, date of birth, birth parity, or weaning weight. The results show that using a combination of measuring MFD and visually assessing the fleece for staple length, staple definition and crimps can help identify the most profitable Angora goats. In this process, the objective measurement of MFD appears essential. Visual assessment will provide some extra benefit in identifying these animals above that provided by measuring MFD alone. Animal size should be considered by mohair producers when identifying more productive mohair producing animals. © 2014 Elsevier B.V.

Indices for cashmere fleece competition and across farm comparisons: The role of staple length in identifying goats of higher cashmere production

A single focus on mean fibre diameter (MFD, μm) as the definition of cashmere quality overlooks the effects of fibre length, softness and fibre curvature on cashmere processing, textile quality and consumer acceptance. Many farmers overlook the importance of cashmere staple length (SL, cm) in their fleece assessments. We aimed to determine the importance of SL in comparison with MFD when evaluating cashmere production and to identify how across farm comparisons of cashmere fleeces can be objectively undertaken. A sample of 1244 commercial cashmere fleeces from goats originating from many Australian farms was used. Least squares models, relating the logarithm of clean cashmere production (CCMwt, g) to MFD and SL, were fitted. Six years of data from the Australian cashmere industry between farm fleece competitions were analysed to determine the relation between CCMwt and MFD. In the research flocks, adjusting CCMwt of individual goats across farms for MFD only accounted for 2% of the variance, whereas SL accounted for 39% of the variance. The least squares additive model involving only SL was: log10(CCMwt)=1.570+0.06010×SL. Thus CCMwt was proportional to: 100.06010×SL=1.1484SL. It was appropriate to adjust CCMwt for SL by a factor 1/1.1484(SL-SL0) where SL0 is a standard SL of 7.5cm. The between farm index for cashmere weight equals: cleancashmerestaplelengthindex=2.823×CCMwt/1.1484SL. For industry fleece competitions, regression analysis indicated that there was no association between cashmere production and MFD (P=0.81), similar to the research data. Adjusting CCMwt for MFD in across farm comparison and fleece competitions appears to be ineffective. For farm comparisons and in fleece competitions it is important to assess cashmere SL. The use of the Clean Cashmere Staple Length Index will provide a more robust comparison of cashmere productivity between farms as it is an indirect indicator of desirable skin secondary follicle development. The results have application in development projects where obtaining a cashmere MFD test is costly or unavailable. © 2013 Elsevier B.V.

The influence of yarn parameters on the ultraviolet protection of yarns

 Improving ultraviolet (UV) protection of textiles is essential to protect wearers against UV radiation induced risks. In addition to fabric parameters, yarn parameters are important factors affecting UV protection of textiles. This work is to examine the influence of yarn parameters on UV protection in order to set up a statistical model for predicting the UV protection of yarns. Wool yarns with different variables were used to test the ultraviolet protection factor (UPF) values for data analysis and the model verification. The model provides the optimized parameters for the UV protective fabric design. This work is helpful as a pre-cursor to the development of a more advanced optical model, which will look at understanding the penetration of UV light through fibres, yarns and fabrics.

Relationships between sleeve trial and wearer trial assessment of discomfort and objective measurements

The relationships were investigated between the prickle discomfort scores, assessed by human response from wearer trial garment assessment, and sleeve trial, Wool ComfortMeter (WCM) and Wool HandleMeter (WHM) assessments of fabrics, and fiber diameter characteristics including mean fiber diameter (MFD). Sleeve trial assessment followed exercise, the use of a control sleeve to reduce participant variance and four sensory traits. WHM provides eight handle parameters calibrated against a panel of experts. Four scenarios were evaluated: sleeve trial assessment with MFD; sleeve trial assessment with MFD and WCM; sleeve trial assessment with MFD, WCM and WHM parameters; and sleeve trial assessment with WCM and WHM parameters. Data were analyzed using correlation and forward stepwise general linear modeling. There was no evidence that the incidence of fibers coarser than 30 µm aided the prediction of prickle discomfort once MFD had been accounted for in the models. There were significant correlations between the WCM measurement and each sleeve trial attribute. There was no significant correlation between WHM parameters and sleeve trial assessments. The sleeve trial attribute of ‘skin feel’ offers potential to improve the predictions made of wearer trial prickle discomfort when used in association of the WCM with or without data on fabric MFD. There was little evidence to support using WHM parameters with or without the WCM in predicting wearer assessed prickle discomfort of fabrics. These results indicate that the rapid evaluation of fabrics using sleeve trial assessment can provide cost effective ranking of consumer preferences.

Visible and UV functionality of TiO2 ternary nanocomposites on cotton

This research intends to increase the photocatalytic efficiency of cotton fabrics coated with TiO2-based nanocomposites under illumination particularly visible light. The fabrics were functionalized using a low-temperature sol-gel method of TiO2/Metal/SiO2 nanocomposite systems. Integrating silica and noble metals into TiO2 sol was put forth for boosting its functionality. Three noble metals (gold (Au), platinum (Pt) and silver (Ag)) with four different concentrations were employed. The photocatalytic activity of the functionalized fabrics was assessed through coffee stain-removal test and photodecomposition of methylene blue (MB) under UV and visible light. The impact of coating layers on fabrics' hydrophilicity was analyzed through measuring the water contact angle as well as the water absorption time. The fabrics were characterized using XRD, SEM and EDS. It was corroborated that the presence of silica enhanced the self-stain-removal capability of fabrics under UV. Moreover, the self-cleaning property of fabrics improved under both UV and visible light after integrating the metals into the colloids. In the same line, the self-cleaning activity threshold of fabrics was shifted to visible region.