Nuray Ucar

Predicting Bursting Strength of Cotton Plain Knitted Fabrics Using Intelligent Techniques

The bursting strength of cotton plain knitted fabrics is predicted before manufacturing using intelligent techniques of neural network and neuro-fuzzy approaches in this re search. Among many parameters that affect fabric bursting strength, fabric weight, yarn breaking strength, and yarn breaking elongation are input elements for the predictions. In this research, both the multi-layer feed-forward neural network and adaptive network- based fuzzy inference system, a combination of a radial basis neural network and the Sugeno-Takagi fuzzy system, are studied. Both systems have the ability to learn training data successfully, and testing errors are small enough to give an approximate knowledge of the bursting strength of the fabric to be knitted.

Predicting Circular Knitting Machine Parameters for Cotton Plain Fabrics Using Conventional and Neuro-Fuzzy Methods

Although there are many studies related to predicting the dimensions of knitted fabrics, there are no studies available about predicting the knitting machine used to produce the knit. Until now, the decision to select a knitting machine was made through experience, trial and error, or rough calculations. This study predicts the machine gauge and diameter more accurately for cotton plain knitted fabrics. Both conventional (multiple linear regression) and neuro-fuzzy methods are used for the predictions. High correlation coefficients are obtained with multiple linear regression analysis. A neuro-fuzzy method using an adaptive network based fuzzy inference system (ANFIS) is also used for predic tions, and the results of both systems are compared.

Investigating the Drape Behavior of Seamed Knit Fabrics with Image Analysis

Drape is one of the most important fabric aesthetic properties. Although there are many studies related to the drape structure of seamless fabrics, knowledge about the drape behavior of seamed fabrics is very limited. This study analyzes the effect of five-thread overlock seams (stitch type 516, seam type Ssa-1) on the drape behavior of heavy weight knit fabrics to provide prediction equations for drape. Results are statistically analyzed. From the regression analysis, the drape coefficients of seamed heavy weight knit fabrics and the rating values obtained from a subjective analyses are predicted with 0.80 and 0.86 correlation coefficients, respectively.

Effect of Lyocell Blend Yarn and Pile Type on the Properties of Pile Loop Knit Fabrics

This paper investigates some physical properties of pile loop knit fabrics. Several fabric parameters, such as pile type (pile loop and cut-pile loop fabrics), fiber type (100% cotton and 50/50% cotton/lyocell blend), fabric tightness (slack, medium, and tight), relaxation (dry relaxation and wash and dry relaxation), are changed. The effects of these parameters on the physical properties of the fabrics, such as dimensional, drapeability, abrasion, and spirality, are analyzed. To determine their relationship and significance, a bivariate correlation analysis and an analysis of variance are conducted. The presence of lyocell and cut-pile loop fabrics increases the lengthwise shrinkage and widthwise extension after repeated wash and dry cycles. Fabric thickness decreases with the presence of lyocell and decreases fabric tightness. Lyocell blend and ground-face fabrics have lower drape coefficients. Spirality tends to increase with the presence of lyocell and pile loop fabrics. Fabric abrasion behavior is also studied.

Physical and comfort properties of the hoisery knit product containing intermingled nylon elastomeric yarn

There are several studies related with knitted fabric containing elastomeric yarn. These studies have been carried out only on fabrics containing naked elastomeric yarn, i.e., without intermingling. And most of them have focused on dimensional and extension-recovery properties of the fabric. Of course, intermingling yarn parameters such as number of knots and draw-ratio will affect the properties and performance of the fabrics. This paper presents a study about the effect of draw-ratio and number of knots, which are important parameters in intermingled nylon-elastomeric yarns, on the physical and comfort properties of hosiery knit products. To see the relationship and significance, bivariate correlation analysis and analysis of variance have been carried out. It has been seen that increase of draw ratio and number of knots lead to an increase in dimensional change, stitch density, fabric weight, and lead to a decrease in fabric spirality, abrasion, fabric wicking (wickability in course direction is less than that of wale direction). Fabric thickness increases with an increase in draw ratio and a decrease in number of knots. The number of knots and the draw-ratio do not affect the fabric drying rate. However, an increase in the draw ratio and the number of knots result in an increase in initial water content before beginning the drying process. But, an increase in initial water content is not so high as to affect the drying rate.

Thermal and mechanical properties of composite nanofiber webs and films containing cellulose nanowhiskers

In this study, nanocomposites reinforced with cellulose nanowhiskers (CNWs) were prepared by employing three different fabrication methods. These methods include electrospinning of nanofiber webs using a single-component nozzle, electrospinning of nanofiber webs using a coaxial bi-component nozzle, and film casting followed by compression molding. Maleic anhydride grafted elastomeric polymer was used as the polymer matrix. Nanocomposite samples obtained from these three different systems were characterized in terms of morphology, and mechanical and thermal properties. The processing–structure–property relationships of the nanocomposites are discussed in this paper.

The Effects of Super Absorbent Fibers on the Washing, Dry Cleaning and Drying Behavior of Knitted Fabrics

In this study, water absorption and drying properties of knitted fabrics produced by 100 % polyester staple fibers (PET) yarn, blend of 80 % PET, 20 % super absorbent fibers (SAF) yarn and covered 80—20 % PET-SAF blend yarn, which the surface of the 80—20 % PET-SAF blend yarn has been covered by a monofilament polyester were experimentally examined. The effect of SAF, covering yarn, washing and drying treatment and dry cleaning treatment on the water absorption of the fabrics was analyzed. It was seen that knitted fabric with 80—20 % PET-SAF blend yarn and covered blend yarn always had higher water absorption value and longer drying time than knitted fabric with 100 % PET. However, knitted fabric with covered blend yarn had less water absorption than the fabric with blend yarn. Water absorption values of fabrics did not change too much during repeated water absorption tests. The absorption properties of the fabrics containing SAF decreased dramatically after washing and drying treatment. However, after repeated dry cleaning treatment, there was still considerably high water absorption capacity on the fabric containing SAF with regard to the fabric with 100 % PET.

Water vapor absorption properties of a novel filament composed of maleic anhydride polypropylene, polypropylene and super absorbent polymer

The aim of this study is to develop a prototype filament that can absorb water vapor without creating any feeling of wetness and can be durable against the cleaning processes. A blend of polypropylene (PP) and maleic anhydride polypropylene (MAPP) is used for the outer surface; super absorbent polymer is placed into the cavity of prototype filament. The new prototype filament can absorb water (approximately 23%) without creating any feeling of wetness and dries totally in 20 minutes. Different blend ratios have been investigated for water vapor absorbency after washing treatment and it has been found that 50% MAPP—50% PP blend with high super absorbent polymer has better washing performances.

Synergistic effect of polyaniline, nanosilver, and carbon nanotube mixtures on the structure and properties of polyacrylonitrile composite nanofiber

In this study, various amounts of carbon nanotubes (CNTs), nanosilver (AgNPs), and polyaniline (PANI) were incorporated at the same pot into the structure of composite polyacrylonitrile (PAN) nanofibers, which were produced by electrospinning process in order to see synergistic effect of the additives on the final properties of the composite materials. Performance and characteristic properties of composite nanofibers were analyzed by tensile tester, electrical conductivity meter, Fourier Transform Infrared Spectroscopy, differential scanning calorimetry, X-ray diffraction, scanning electron microscopy, and antimicrobial activity test. Statistical analysis (analysis of variance) was performed to see whether the differences were statistically significant or not. It was seen that samples with AgNPs had higher breaking strength and electrical conductivity than the samples with CNTs. Generally, PANI improved the crystallinity of the composite material more than the nanoparticles (CNTs and AgNPs). Even though each of the nanoparticles was used in low concentrations, the composite materials (PAN–1CNT–1AgNO3–R and PAN–PANI–1AgNO3–R) gained antimicrobial properties due to the synergistic effect of additives. The results suggested that PAN composite nanofibers with 3 wt% PANI and 1 wt% AgNO3 generally presented better performance than the other samples in terms of electrical conductivity, antimicrobial activity, mechanical strength, crystallization, and thermal stability.

Polyacrylonitrile-polyaniline composite nanofiber webs: Effects of solvents, redoping process and dispersion technique

This study was carried out to examine the effect of different solvents (DMSO, NMP, DMF) and solvent mixtures, application of dispersion and mixing techniques during solution preparation and redoping process on polyacrylonitrile (PAN) and camphorsulfonic acid (CSA) doped polyaniline (PANI) composite nanofibers. It was observed that nanofibers produced from DMSO and NMP solvents had larger fiber diameters than nanofibers produced from DMF. When the crystallinity of the 100 % PAN nanofibers were compared, the nanofibers electrospun from DMSO had the lowest crystallinity values. The tensile breaking stress values of the nanowebs produced from DMSO and NMP were higher than nanowebs produced from DMF while the breaking elongation values of the nanowebs produced from DMF was higher. Mechanical dispersion technique resulted in higher tensile breaking stress values than corresponding magnetic stirring. The redoping process also affected the tensile properties of the nanowebs by increasing the breaking stress values and decreasing the breaking elongation values. When DMSO was used as a solvent for the production of composite nanofibers, the electrical conductivity values at around 10−6 S/cm were obtained corresponding to the semiconductive material range. The use of solvent mixtures resulted in better conductivity values than their counterparts. When CSA-NMP and CSA-NMP/DMF were compared, the nanofibers produced from the solvent mixture had higher conductivity values. On redoping, the conductivity increased 10 times and reached 1.2×10−5 S/cm. The reference samples with DMSO had the lowest cyclization temperature and enthalpy. Addition of PANI increased the thermal stability of the composite nanofibers in comparison with pure PAN.