Emel Onder

Effects of Different Structural Parameters on Carpet Physical Properties

This paper deals with some of the physical properties of face-to-face woven carpets with different structural parameters. Based on appearance retention, abrasion resistance, and tuft withdrawal tests, effective parameters of carpet quality are determined by variance and regression analyses, and the changing characteristics are emphasized in order to direct attention to weaknesses, which are important for total carpet performance.

A Comprehensive Stress and Breakage Analysis of Staple Fiber Yarns Part I: Stress Analysis of a Staple Yarn Based on a Yarn Geometry of Conical Helix Fiber Paths

This paper, which is a preliminary to a general investigation of the stress-strain and breakage behavior of staple yarns, deals with the stress analysis of a staple yarn under axial strain, based on an ideal yarn geometry that allows for fiber migration, assuming conical helix fiber paths. The position and dimensions of a yarn element based on this conical helix model are defined first, in relation to yarn dimensions, and the radial equilibrium conditions are obtained. The axial stress at any point on the yam cross section under a given strain is then expressed by using the characteristic stress-strain curve of the fiber for both small and large strains. Thus the stress distribution over the cross section can also be determined.

Influence of Varying Structural Parameters on Abrasion Characteristics of 50/50 Wool/Polyester Blended Fabrics

This paper reports an analysis of the influence of polyester and yarn type on the abrasion resistance of 50/50 wool/polyester blended woven fabrics. Recently developed polyester fibers put into the blend and two-strand Sirospun yams are compared with 2.5 denier standard polyester and two-fold ring yarns. Mass losses of ten fabrics abraded in the Martindale tester are obtained for eight abrasion levels and given in three groups of graphs in a comparative form. Regression analyses help describe mass loss ratios of fabrics as a function of abrasion cycles and other structural parameters. Linear and, in some cases, quadratic and cubic models help explain the acceleration in mass loss rates, and SEM photographs show surface degradation of wool blend fabrics.

Electroless silver coating on glass stitched fabrics for electromagnetic shielding applications

In this study silver nanoparticles were deposited by electroless coating onto glass-stitched fabrics via the Tollens’ reaction for technical textile applications. The effect of fabric compactness and the amount of silver nitrate solution on conductivity and electromagnetic interference shielding effectiveness (EMI SE) were studied. The results showed that a compact fabric surface promoted the EMI SE and that a critical threshold of surface conductivity of 0.3 S.cm–1 was required to obtain an EMI SE above 50 dB in the frequency range 300 MHz−1.5 GHz. Using SEM analysis we found that conductivity values were compatible with the coating thickness of samples. FT–IR analysis revealed that the presence of Ag particles caused the aliphatic C–H stretching frequencies (2858 and 2927 cm–1) to become shifted to higher values (2901 cm–1, and 2988 and 2972 cm–1, respectively).

Influence of varying structural parameters on the properties of 50/50 wool/polyester blended fabrics

This paper deals with the mechanical properties and air permeability of lightweight wool blend apparel fabrics. We have studied mechanical responses in uniaxial tensile and tear tests of gray-state fabrics, and low deformation characteristics (i.e., bending rigidity, shear rigidity, and extensibility) in FAST tests of finished fabrics. We also measure fabric drape coefficients and node numbers using Cusicks method and fabric air permeabilities. Effects obtained by changing polyester and yarn type are analyzed for three groups of fabrics with different constructions using a statistical approach and are found to be significant; however, using novel polyester with a special cross-sectional shape and varying fineness in the wool blend, we successfully obtain fabrics with low rigidities, better drape characteristics, and quite sufficient tensile and tear performance. The behavior of fabrics woven with Sirospun yams is quite satisfactory in many respects. Polyester and yarn type also significantly affect fabric air permeability.

A Comprehensive Stress and Breakage Analysis of Staple Fiber Yams Part II: Breakage Analysis of Single Staple Fiber Yams

This paper contains the theory developed to describe the breaking mechanism of single staple fiber yams, based on the ideal conical helix model and the stress and breakage theory given in Part I. The computer analysis program is based on an al gorithm describing the slipping and gripping behavior of the fibers leading to final breakage. For verification of the theory, single worsted yams are tested for constant rate of extension strength.

Smart Protective Clothing for Aircraft Crew

Using smart and functional materials in textile applications has gained much more importance over the last decade in order to provide and improve some specific end product properties. In the present work, we designed spacer weft-knitted fabrics for the purpose of protective clothing – which has an electromagnetic shielding effect and a good thermal property – of aircraft crew. To provide two functions in one fabric, spacer weft-knitted fabrics composed of inherently thermally perfect wool and electrically conductive silver-plated nylon yarns were developed initially. The application of temperature-responsive polymer (TRP) and phase change material (PCM) onto these fabrics was then performed in order to enhance their thermal properties. The structural characterizations and thermal analyses performed showed that the developed fabrics demonstrated not only much better electromagnetic shielding effect but also improved thermal performance than ordinary clothing as underwear.