Volume 12 (2012): Issue 1 (March 2012)

Polyacrylonitrile (PAN) nanofibres and carbon nanotube (CNT) reinforced PAN nanofibres were successfully electrospun. A polymer plasticiser, ethylene carbonate (EC), was added into the PAN/CNT solutions. The average diameter of the fibres varied between 80 and 240 nm. This study investigated the effects of polymer concentration, CNT and EC on the morphological characteristics of electrospun PAN fibres. Electrospinning parameters were set at constant values to prevent their mutual influences on the resultant morphology. It was observed that increasing the polymer concentration led to a reduction of beads density and an increase in the diameter of the PAN nanofibres. The fibre diameters also increased as a result of the addition of CNTs below the electrical percolation threshold. It was found that the inclusion of EC permits changes in the morphological characteristic of the PAN/CNT nanocomposite fibre regardless of the effects of its conductivity and viscosity

The possibility of new and objective evaluation of yarn appearance wound on the board is described. A statistical method which has previously been used for the evaluation of surface unevenness of flat textile - semivariograms is used. The yarn board appearance is converted into a grey-scale image and the fluctuation in degrees of greyness between square fields in the image is evaluated by semivariogram. This method was applied on standard yarn boards from the standard CSN 80 0704 in addition to real yarn boards. The results of semivariograms constructed from a simulated ideal appearance of yarn on the board are discussed with the aim of introducing an ideal case behaviour of semivariograms. The possibility of using this function for the objective evaluation of yarn board appearance is also discussed.

This paper is concerned with the drive of small-diameter knitting machines and its optimal structure in reference to the knitting process. Based on an analysis of existing machines, a new structure is proposed employing controlled drives. In this proposal, emphasis has been laid on minimising the consumption of electric power and on simplifying the mechanical section of the structure. An analysis of the dynamic characteristics of the newly proposed concept, and a comparison with existing machines has been carried out.

Wound assessment has become an important issue in the wound treatment procedure. One important indicator of the wound status is the pH value. Our approach to assess this quantity is through use of a fiber sensor coated with a pH-responsive hydrogel, which functions as a sensitive layer for impedance measurements. An advantage of this is its integratability into wound dressings using standard textile technologies. The pH characteristic shows a pH-dependent behavior of the absolute impedance at certain frequencies. The fabrication technology and sensor characteristics are discussed. The values of almost 14% impedance change demonstrate the potential for improvement by optimizing fabrication technologies. The presented sensor meets all requirements necessary for wound pH assessment

The use of clean water in textile finishing is both common and very expensive. Effluent water subjected to advanced methods of physical, chemical, and biological treatment could be used for this purpose. However, information obtained from industry and the literature shows that effluent water obtained from different finishing processes may be reused without being totally purified. In this paper, a method is proposed to determine the viability of reusing effluent water obtained from different textile finishing processes of cotton fabrics after just basic treatments. These treatments include; filtering, airing, pH regulating and ion exchange. Effluent water obtained in different textile finishing processes was analysed in terms of pH value, COD (Chemical Oxygen Demand), SS (Suspended Solids), colour, hardness and conductivity. Effluent water for treatment and the process where the treated water was reused were determined by means of the proposed method, based on a multiple criteria decision making approach. A laboratory scale trial was conducted to investigate the efficiency of treatment.