Ali Afzal

Statistical model for predicting the air permeability of polyester/cotton-blended interlock knitted fabrics

The aim of this study is to model the effect of knitting parameters on the air permeability (AP) of polyester/cotton interlock fabrics. Fabric samples of areal densities ranging from 105 to 654 g/m2 were knitted using yarns of three different polyester/cotton blends, each of the three different linear densities by systematically varying knitting loop lengths for obtaining different cover factors. It was found that changing the polyester/cotton blend ratio from 65/35 to 52/48 and 40/60 did not have a statistically significant effect on the fabric AP. AP sharply decreased with decrease in knitting loop length owing to increase in fabric areal density. Increase in yarn linear density (tex) resulted in a decrease in AP due to increase in fabric thickness as well as the areal density. It was concluded that response surface regression modeling could adequately model the effect of knitting parameters on the fabric AP. The model was validated by unseen data-set and found that predicted and actual values were in good agreement with each other with less than 5% absolute error. Sensitivity analysis was also performed to determine the relative contribution of each input variable on the AP of the interlock fabrics.

Geometrical model to calculate the consumption of sewing thread for 301 lockstitch

Sewing thread is one of the most basic yet important components of a garment. Thread consumption for the lockstitch (Class 301) can be calculated by using its geometrical shape. This paper aims to develop a geometrical model to calculate the thread consumption for lockstitch (Class 301). Based on the basic geometry of lockstitch, a model has been proposed. The model is derived mathematically taking into account different variables: stitch length, stitch density, material thickness, and interlacing. Finally, the model was verified for 19 samples by comparing actual thread consumption with predicted thread consumption. The proposed model predicts the thread consumption with 97% accuracy. Sensitivity analysis is also performed to determine the significant influencing factor affecting the thread consumption. The proposed model can predict the thread consumption precisely for 301 lockstitch. Therefore, this model is useful for the apparel industry.

Prediction and Correlation of Air Permeability and Light Transmission Properties of Woven Cotton Fabrics

Abstract The aim of this study was to develop statistical models for predicting the air permeability and light transmission properties of woven cotton fabrics and determine the level of correlation between the two parameters. Plain woven fabrics were developed with different warp and weft linear densities, ends per inch and picks per inch. After desizing, scouring, bleaching, drying and conditioning, the air permeability and light transmission properties of the fabric samples were determined. Regression analysis results showed statistically significant effect of the fabric ends, picks and warp linear density on both the fabric air permeability and light transmission. Correlation analysis was performed to analyze the relation between the fabric air permeability and light transmission. A linear equation was also formulated to find the fabric air permeability through transmission of light intensity. A fitted line plot between the air permeability and light transmission exhibited significant correlation with R-sq. value of 96.4%. The statistical models for the prediction of fabric air permeability and light transmittance were developed with an average prediction error of less than 7%.

Influence of Fabric Parameters on Thermal Comfort Performance of Double Layer Knitted Interlock Fabrics

Abstract The aim of this study was to analyse the effects of various fabric parameters on the thermal resistance, thermal conductivity, thermal transmittance, thermal absorptivity and thermal insulation of polyester/cotton double layer knitted interlock fabrics. It was found that by increasing fibre content with higher specific heat increases the thermal insulation while decreases the thermal transmittance and absorptivity of the fabric. It was concluded that double layer knitted fabrics developed with higher specific heat fibres, coarser yarn linear densities, higher knitting loop length and fabric thickness could be adequately used for winter clothing purposes.

Effect of Weave Structure on Thermo-Physiological Properties of Cotton Fabrics

Abstract This paper aims to investigate the relationship between fabric weave structure and its comfort properties. The two basic weave structures and four derivatives for each selected weave structure were studied. Comfort properties, porosity, air permeability and thermal resistance of all the fabric samples were determined. In our research the 1/1 plain weave structure showed the highest thermal resistance making it suitable for cold climatic conditions. The 2/2 matt weave depicted the lowest thermal resistance which makes it appropriate for hot climatic conditions.

Investigation and modeling of air permeability of Cotton/Polyester blended double layer interlock knitted fabrics

The aim of this study was to analyze and model the effect of knitting parameters on the air permeability of Cotton/Polyester double layer interlock knitted fabrics. Fabric samples of areal densities ranging from 315–488 g/m2 were knitted using yarns of three different cotton/polyester blends, each of two different linear densities by systematically varying knitting loop lengths for achieving different cover factors. It was found that by changing the polyester content in the inner and outer fabric layer from 52 to 65 % in the double layer knitted fabric did not have statistically significant effect on the fabric air permeability. Air permeability sharply increased with increase in knitting loop length owing to decrease in fabric areal density. Decrease in yarn linear density (tex) resulted in increase in air permeability due to decrease in areal density as well as the fabric thickness. It was concluded that response surface regression modeling could adequately model the effect of knitting parameters on the double layer knitted fabric air permeability. The model was validated by unseen data set and it was found that the actual and predicted values were in good agreement with each other with less than 10 % absolute error. Sensitivity analysis was also performed to find out the relative contribution of each input parameter on the air permeability of the double layer interlock knitted fabrics.

Development of multifunctional different cross-sectional shaped coaxial composite filaments for SMART textile applications

The aim of this study is to design a spinneret that can be used efficiently for the manufacturing of coaxial composite filaments. Poly(ethylene terephthalate) was used as resin matrix with 99.9% pure copper filament as the core. The characterization of the polymer was done to determine polymer thermal and rheological properties. Multi-shaped coaxial composite filaments were obtained after successful laboratory-scale melt extrusion machine modification and spinneret development. The cross-sectional surface and shape were analyzed with a scanning electron microscope. Coaxial filaments having the cross-section including elliptical, triangular, rectangular and circular shapes were developed. The characterization of spinneret design and coaxial composite filaments were also reported. The effect of spinneret design parameters on the cross-sectional shape of the filament were analyzed.

Development of Environment Friendly Bio Cross-Linker Finishing of Silk Fabric

Silk fabric easy care performance was assessed by using carboxylic acids. Cross-linker used in this study was citric acid, while sodium hypophosphite (SHP) was incorporated as a catalyst for cross-linking with silk. Enhancement in the easy care performance and shrinkage was obtained after treatment with citric acid. In addition, formic acid was used as swelling agent and treated fabric exhibited superior performance when it was incorporated in the recipe of citric acid. Antimicrobial performance of the silk fabric was also enhanced by using the above mentioned formulation.

Characterization and antibacterial property of Kapok fibers treated with chitosan/AgCl–TiO2 colloid

Abstract The aim of this research is to investigate the antibacterial activity of Kapok fibers modified with AgCl/TiO2 and Chitosan colloid. A very simple, single-step (pad-dry-cure) method was used for the application of AgCl/TiO2 and Chitosan colloid on kapok fibers, the chemicals used are easily available. Different blend ratios of chitosan and AgCl/TiO2 colloid were applied to the bleached kapok fibers and antibacterial properties were assayed against gram positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. The treated kapok fibers were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). It was observed that the bacterial growth was significantly reduced in the samples which had a higher concentration of chitosan and AgCl/TiO2 colloid. However, a significant reduction in bacterial growth with the use of this colloid was observed.

Statistical analysis of yarn to metal frictional coefficient of cotton spun yarn using Taguchi design of experiment

Yarn’s surface to metal friction is an important consideration in the subsequent process of knitting and weaving as it influences mainly the ends down rate, fly generation, process efficiency, wear and tear of machine parts, and production rate of the process. These frictional properties are measured in terms of the coefficient of friction of yarn. The effect of cotton type, yarn twist, yarn linear density, process type, and finishing treatment was studied on the surface to the metal friction coefficient of cotton spun yarn using Taguchi experimental design. The experiments were conducted with Pakistani and Indian cotton using combed and carded ring spinning processes. Using Taguchi design of experiment, a total of 36 samples of cotton ring-spun yarns were produced. The coefficient of friction between the yarn’s surface and metal’s surface is measured in compliance with ASTM D3108. The outcome of the Taguchi model to predict the coefficient of friction of yarns with a predefined combination of constituting parameters was further confirmed with nine yarn samples. The frictional characteristics of yarns are found to be influenced by all factors. In addition to the application of wax, the longer fiber length, lower trash count, lower short fiber index, and the optimum level of twist are found advantageous to reduce the yarn coefficient of friction.