α-Amylase immobilization on amidoximated acrylic microfibres activated by cyanuric chloride

Enzyme immobilization is one of the most important techniques for industrial applications. It makes the immobilized enzyme more stable and advantageous than the free form in different aspects. α-Amylase was immobilized on 4% cyanuric chloride-activated amidoximated acrylic fabric at pH 7.0 with (79%) maximum efficiency. A field emission scanning electron microscope and Fourier transform infrared were used to confirm the immobilization process. Even after being recycled 10 times, the immobilized enzyme lost just 28% of its initial activity. Owing to immobilization, the pH of the soluble α-amylase was shifted from 6.0 to 6.5. The immobilized α-amylases showed thermal stability at 60°C, and became more resistant to heavy metal ions. The k m values of the immobilized and soluble α-amylases were 9.6 and 3.8 mg starch ml −1 , respectively. In conclusion, this method shows that the immobilized α-amylase proved to be more efficient than its soluble form, and hence could be used during saccharification of starch.

Effect of the fabric color on the visual perception of pilling

Purpose Pilling is a fabric surface fault comprising of small, fuzzy balls on the surface of a fabric that leads to poor handle and quality. The purpose of this paper is to investigate the effect of the fabric color in terms of depth and hue on the visual perception of pilling on the fabric surface. Design/methodology/approach Acrylic fabrics were prepared at various color depths and hues and then were applied with relatively equal amount of pilling on the surface of samples. The amount of perceived pilling was evaluated by human observers by employing paired comparison method and the results were analyzed using statistical methods. Findings According to the results, color depth and the visual perception of pilling in achromatic sample were nearly independent. Color hue can be considered as an important factor in the visual perception of pilling so when the color contrast between the pill and background decreases, the visual perception of pilling decreases as well. Hence, the achromatic sample have the most amount of pilling perception whereas green and blue samples show less pilling, in visual sensation. Originality/value There is a strong demand for acrylic fabrics in apparel industry but they have high tendency for pilling formation. To overcome this problem, experts have suggested some methods to prevent or reduce pilling. If it is proved that color influences on pilling perception, an useful instruction will be available for acrylic fabric manufacturers in order to satisfy their customer with good quality of products. In this work, the authors tried to find such relationships between the color and the pilling perception for human observers.

Polyurethane cum hydrophobic finishing of acrylic fabrics for enhanced comfort characteristics

Purpose The paper aims to improve the protective and comfort properties of both woven and knitted acrylic fabrics by applying a hybrid waterborne polyurethane/fluorocarbon hydrophobic finish. Design/methodology/approach In this study, it was found that the transportation of water from fabrics is one of the important textile parameters. To improve this property, a polyurethane-based finish (Dicrylan BSRN®) and an oil- and water-repellent finish (Oleophobol ZSR®) were applied by using the pad-dry-cure method. After applying the finishes, the resultant fabric samples were investigated for various textile properties. Findings The application of Oleophobol ZSR® increased the absorbency time, indicating that the fabric became hydrophobic, whereas the application of Dicrylan BSRN® finish improved the moisture management properties of the woven acrylic. The tensile strength of the woven acrylic fabric was not significantly affected by the application of these finishes. The contact angle of treated knitted fabrics increased and air permeability decreased with an increase in the concentration of Oleophobol ZSR®. Practical implications Moisture management is one of the crucial performance criteria in today’s apparel industry. Therefore, fluorochemicals are one of the major precursors used in water-repellent finishes and waterproof membranes in outdoor garments. Based on this fact, this research work focused on the textile sector, where moisture management is required. Originality/value This is the first report about the combined application of waterborne polyurethane and fluorochemical-based finishes on acrylic fabrics to tune their comfort and hydrophobic properties.