No abstract

Polyethylene terephthalate (PET), as the most favorable packaging material, is owing to its transparent color, lightweight, strength, food safe, inexpensive price, fully recyclability, etc. In addition to all these advantages, PET as a waste material takes up considerable space in nature and needs to be recycled for the disposal of these wastes. In this regard, recycling enables conserving raw materials, reducing energy use in order to produce virgin PET, and reducing greenhouse gas emissions. Today, PET is the most widely recycled plastic in the world. Eco-friendly products obtained by recycling of PET are mainly used as textile fibers. In addition, both brands and consumers are seen to be enthusiastic in order to minimize the environmental effects of PET wastes. This study is concerned with the use of textile fiber from recycled PET (r-PET) bottles to produce a cotton blended ring and compact yarns. Undoubtedly, the study also includes comparison of cotton blended virgin polyester fiber (v-PET) with r-PET fiber to determine the advantages and disadvantages of r-PET fiber. The reason for choosing cotton fiber is the most preferred fiber blending with PET commercially.

In this article, porosity and air permeability of denim fabric produced from filament core-spun yarns with different filament fineness and yarn linear density were demonstrated. For this purpose, 110 dtex drawn textured polyester filaments with conventional, fine, and micro finenesses were used as core part, and combed cotton fiber was used as sheath part to obtain core-spun yarns with four different yarn linear density on a modified ring spinning system with the same spinning parameters. Besides the production of core-spun yarns, 100% cotton ring-spun yarns were produced as control group at the same conditions for each yarn linear density, as well. To evaluate the effect of filament fineness and yarn linear density on air permeability and total porosity, denim fabrics were obtained by using 24 yarn samples as weft at the same cover factor with four determined weft densities. Results showed that filament fineness and yarn linear density have a significant effect on total porosity and air permeability at a significance level of 0.05. In addition, high correlation (79.4%) between air permeability and total porosity of denim fabric samples was observed at a significance level of 0.01.

Elastic core-spun yarns which is used as weft yarn for textile fabrics gained great importance in the last decade its due to the fact that stretch and recovery, comfort fits and flexibility properties. The technological progress made the dual core-spun yarn production possible. The dual core-spun yarns are composed of filament that contributes durability and polyurethane based elastane that provides stretchability to the fabrics. Hereby, both filament and elastane characteristics have great influence on denim performance at the same time. The main purpose of this study is to achieve the effect of filament fineness and elastane draft on denim fabric performance such as breaking force, breaking elongation, tear force, vertical elastic recovery, moisture management that is wicking rate and water absorption properties. Meanwhile, filament core-spun yarns with different filament fineness and 100% cotton yarn were also used as weft of the denims in order to investigate the differences statistically. It was found that that filament fineness and elastane draft had statistically significant effect on all inspected performances of denim fabrics except water absorption.

Denim fabric is one of the most popular casual wear fabrics worldwide. The performance characteristics of denim fabrics have been improved by using functional fibers and elastane to make them comfortable to wear. Elastane fibers with high elasticity are used extensively in denim fabric production. Elastane fibers are generally used as the core part of the core-spun yarns as weft yarns. Besides elastane fibers; polyester and polyester derivatives are commonly used. This study examines the effects of filament fineness and yarn count on denim fabric performance. Textured polyester filaments with medium, fine and micro linear densities were used as the core part of the core-spun yarn and cotton fiber was used as sheath material. Yarn samples manufactured with the same production parameters at different yarn count were used as weft yarns of denim fabrics. Denim fabrics were produced with the same fabric cover factor to eliminate yarn count difference effects. Tensile, static tearing and dynamic tearing properties of denim fabrics were determined. To evaluate the effects of core part, 100 % cotton denim fabric was manufactured and tested. Statistical analysis was performed to analyze the significance of filament fineness and yarn count ratio. Results showed that there was a significant effect of filament fineness on tensile, static tearing and dynamic tearing properties of denim fabrics. In addition, it was found that yarn count had no significance effect on static tearing properties of denim fabrics.