Effects of laundering on conductivity of polypyrrole-coated textiles

This study examines the resistance change in conductive polypyrrole-coated PET fabrics under the AS 2001.4.15 – 1994 laundering test conditions. The effects of individual detergent components of a standard detergent, including auxiliary chemicals, at four different temperatures were studied. When the coated fabric was washed under the AS 2001.4.15-1994 conditions, the ECE reference detergent and pure soap flakes (sodium sterate) both decreased the conductivity of the coating at a rate exponentially proportional to the laundering temperature. Detergent types had an influence over the rate of degradation; pH conditions had a large influence on the rate of polymer deterioration with the acidic nonionic detergent giving rise to significantly improved laundering conditions. The auxiliary chemicals, sodium carbonate and sodium perborate were seen to cause large degradation of polymers during laundering. Ethylene diamine tetra acetic acid was seen to have only a slight influence on the reduction of conductivity of polymers.

Image processing and pattern recognition in textiles

Image processing and pattern recognition have been successfully applied in many textile related areas. For example, they have been used in defect detection of cotton fibers and various fabrics. In this work, the application of image processing into animal fiber classification is discussed. Integrated into / with artificial neural networks, the image processing technique has provided a useful tool to solve complex problems in textile technology. Three different approaches are used in this work forfiber classification and pattern recognition: feature extraction with image process, pattern recognition and classification with artificial neural networks, and feature recognition and classification with artificial neural network. All of them yieldssatisfactory results by giving a high level of accuracy in classification.

Evaluation of bast fibre retting systems on hemp

In this paper the effect of eight different retting methods on decorticated hemp skins were analyzed. The methods were taken from six publications that looked at the retting of different bast fibres such as ramie, flax and kenaf. The fibres were batch retted in a package dye-vat at 100oC under 2 bar of pressure. The rinsed fibres were opened twice using a Shirley cotton trash separator. The opened fibre was assessed for fibre width, fibre width variation, colour and handle. It was found that the fibre that had undergone chemical retting with 7% Sodium Hydroxide (NaOH) and 0.5% Sodium Sulphite (Na2SO3) had the best diameter (18.39 micron) and the best coefficient of variation of diameter (57.32%). The fibre that was processed with 7% Sodium Hydroxide (NaOH) and 0.5% Sodium Sulphite (Na2SO3) had the whitest colour (YI D1925 = 31.61). The method treated with 1% Sodium Hydroxide (NaOH) and 1% Sodium Sulphite (Na2SO3) had the softest handle and the method treated with 1% Sodium Hydroxide (NaOH) and pre-rinsed with 0.3% Hydrochloric Acid (HCl) showed the best conversion of decorticated skins into spin able fibre (33.9% of dry green skins). It was decided that method treated with 1% Sodium Hydroxide (NaOH) and pre-rinsed with 0.3% Hydrochloric Acid (HCl) had the best fineness of fibre micron, conversion to spin able fibre (33.9% of dry green skins), whitest colour (YI D1925 = 36.13) and softest handle for the cost of chemicals involved.

Determining residual gum content of bast fibres

The measurement of fibre quality in bast fibres is related to the amount of gum (lignin, hemicellulose, wax and pectin) left in the fibre after the retting process. Large amounts of gums present represent poor separation of fibre. Efficiency of retting can be monitored by measuring the residual gum content of the retted fibre.

This paper investigated the use of ultrasonic vibration combined with chemical retting as a pre-treatment to improve accuracy of traditional residual gum content test. Work was conducted on chemically retted hemp fibre. Pre-treatment conditions were analysed by determining the best chemical combination, chemical concentration and treatment time. Fibres were examined for successful separation using optical microscopy and optical fibre diameter analysis (OFDA). The work proposed a new method for determining the residual gum content of hemp fibre.

Changes in fibre curvature during the processing of wool and alpaca fibres and their blends

This paper studied the wool and alpaca fibre curvature and its variation during the fibre processing. It revealed the effect of wool fibre crimp on the cohesion properties of alpaca and wool blended slivers. Different wool and alpaca tops were blended via a number of gillings, and the role of wool fibre curvature in alpaca/wool blend processing has also been investigated. During the wool fibre processing, fibre curvature tended to diminish gradually from scoured fibre to top. Blending wool with alpaca fibres improved the cohesion properties of the blended sliver, compared with pure alpaca slivers. For a high ratio of alpaca component in the blend, a high-crimp wool should be used to achieve good sliver cohesion.