Mustafa E. Üreyen

Regressional Estimation of Ring Cotton Yarn Properties from HVI Fiber Properties

The main aim of the present study was to predict the most important yarn quality characteristics derived from cotton fiber properties that were measured by means of an HVI system. With this aim 15 different cotton blends were selected from different spinning mills in Turkey. The cotton fibers were processed in the short staple spinning line at Ege University Textile and Apparel Research-Application Center and were spun into ring yarns (20s, 25s, 30s and 35s). Each count was spun at three different coefficients of twist (αe 3.8, αe 4.2 and αe 4.6). Linear multiple regression methods were used for the estimation of yarn quality characteristics. Yarn count, twist and roving properties all had considerable effects on the yarn properties and therefore these parameters were also selected as predictors. After the goodness of fit statistics very large R 2 (coefficient of multiple determination) and adjusted R 2 values were observed. Furthermore, analysis of variance tables showed that our equations were significant at the α = 0.01 significance level.

Antibacterial functionalization of cotton and polyester fabrics with a finishing agent based on silver-doped calcium phosphate powders

Textiles are suitable materials for the growth of pathogenic microorganisms. Therefore, various antibacterial finishes have already been developed for textile products. In this work an antibacterial finishing agent containing calcium phosphate-based silver-doped powder was developed for the functionalization of textiles and applied to 100% cotton and 100% polyester knitted fabric samples. Firstly, silver-doped antibacterial powder was synthesized by using a wet chemical method. A size reduction process was applied for reducing the particle size of the powder from micron size to submicron scale. The aqueous dispersion was stabilized by coating the powder surfaces with polyethylene glycol. In order to obtain laundering durability, an aqueous emulsion of an acrylic copolymer was added to the antibacterial solution. The resultant product was applied to all fabric samples by a conventional pad-dry-cure method. The treated fabrics were washed 20 times and the antibacterial efficiency was evaluated after each 10 laundry cycles according to the JIS-L 1902:2002 method against Gram (-) E. coli bacteria. To see the effect of antibacterial finishing on the physical properties of fabrics, the bursting strength, air permeability and color efficiency of the treated and untreated samples were measured and compared. It was found that the antibacterial solution did not affect significantly the bursting strength and color efficiency values of the fabrics, while air permeability was decreased. On the other hand, treated fabric samples preserved their strong antibacterial activities against E. coli after 20 laundry cycles.

Predicting properties of single jersey fabrics using regression and artificial neural network models

In our previous works, we had predicted cotton ring yarn properties from the fiber properties successfully by regression and ANN models. In this study both regression and artificial neural network has been applied for the prediction of the bursting strength and air permeability of single jersey knitted fabrics. Fiber properties measured by HVI instrument and yarn properties were selected as independent variables together with wales’ and courses’ number per square centimeter. Firstly conventional ring yarns were produced from six different types of cotton in four different yarn counts (Ne 20, Ne 25, Ne 30, and Ne 35) and three different twist multipliers (αe 3.8, αe 4.2, and αe 4.6). All the yarns were knitted by laboratory circular knitting machine. Regression and ANN models were developed to predict the fabric properties. It was found that all models can be used to predict the single jersey fabric properties successfully. However, ANN models exhibit higher predictive power than the regression models.

Permeability properties of single jersey fabrics made of hollow yarns

Abstract In this work effect of using hollow yarns on the permeability properties of the single jersey knitted fabrics were studied. Firstly yarns were produced by ring spinning machine using cotton, viscose and acrylic fibres in the mantle and water soluble polyvinyl alcohol (PVA) fibre in the core. Single jersey fabrics were knitted and PVA core was removed subsequently by washing process to create hollow yarn. Weight, air permeability and water transmission rate properties of fabrics were measured before and after washing and compared with reference fabrics. Due to the removal of PVA fibres from the yarn core after washing treatment, air permeability and water vapour transmission rate of the all kind of single jersey fabrics which were produced with hollow yarns increased as well as weight of the fabrics decreased which will cause more comfort during any exercise. It was also found that mantle fibre type and PVA ratio have significant effect on the fabric properties.

Determination of silver release from antibacterial finished cotton and polyester fabrics into water

Abstract Silver compounds have extensive use among the antimicrobial agents in textiles. Silver particles are released into the water during washing processes in particular and they are released from the textile in time due to use. In this work, silver ion release from cotton and polyester antimicrobial fabrics which are the most widely used textiles have been studied. Two well-known silver-based commercial agents and silver-doped calcium phosphate powder-based antibacterial finishing agent which was developed in our previous work were applied to the fabric samples. The release of silver from the fabric samples during washing and incubation was determined by ICP-OES. The effects of fabric composition, time and laundering process on the silver release were studied. It was found that significant amount of silver was released from textile fabrics during washing due to the mechanical forces exerted on the fabrics. The total released silver varied from 73.43 to 92.27% for cotton fabrics and 76.49 to 89.70% for PES fabrics after 20 washing cycles. Results also showed that calcium phosphate can reduce the amount of silver release significantly. It was also found that even a smaller quantity of nanosilver particles was sufficient for strong antibacterial activity.

Thermal characterization and flammability of polypropylene containing sepiolite-APP combinations

Abstract The effects of sepiolite on fire behavior of ammonium polyphosphate-based intumescent flame retardant (IFR)/polypropylene (PP) were investigated. The disaggregation of sepiolite bundles has been provided by wet-milling as the zeta potential value decreased from −9.6 to −31.3 mV. PP and additives were compounded by a twin-screw extruder and molded by injection. A total additive content of 20 wt% in PP and various proportions of sepiolite (1.0–10.0 wt%) in flame retardant (FR) formulation were studied. The flammability of the samples was measured by limit oxygen index (LOI) test and cone calorimetry. The LOI of neat PP (19%) was increased to 32.2% when sepiolite and IFR were used. The peak heat release rate of neat PP (1566.4 kW/m2) was also significantly reduced (94.7 kW/m2) when sepiolite was added with IFR. Thermal analyses results showed that, at higher temperature (700°C), IFR and sepiolite increased the char residue (9 wt%) compared to neat PP (0 wt%).