Muhammet Uzun

Study of the pH and physical performance characteristics of silver-treated absorbent wound dressings

In this study, two common nonwoven fibrous dressings, based on carboxymethylcellulose and alginate, and their silver-treated forms were evaluated in order to compare their performance characteristics including fluid handling capacity, the mechanical properties, and the thermal behavior. The effect of immersing the dressings in the two fluids (solution A and distilled water) on pH was also studied. The results show some clear differences between the untreated and silver-treated dressings, for example the fluid handling and the swelling values of the dressings were reduced due to silver treatment. More considerably, changes were observed in the tensile properties which were decreased when these dressing were treated with the silver. There was no considerable effect on the thermal characteristics of the dressings upon the silver treatment. Statistically significant differences were observed in the pH over time for all tested specimens and also for both test fluids.

KONVANSİYONEL VE KOMPAKT RİNG İPLİK EĞİRME YÖNTEMLERİNİN DOKUMA KUMAŞ MUKAVEMET VE TERMAL ÖZELLİKLERİNE ETKİLERİNİN İNCELENMESİ

In this study, 65/35% polyester/cotton woven fabrics, which were produced by making use of conventional and compact ring spun yarns, were tested and analysed in terms of tensile and thermal comfort properties. The main purpose of this study is to highlight the effects of compact ring spinning on thermal comfort properties of woven fabrics. Investigation of comfort properties were carried out by using Alambeta and Permetest instruments. It is concluded from the results that spinning techniques have a significant impact on the thermal comfort and tensile properties of the tested fabrics.

Thermal conformability of developed fibrous wound dressings

Alambeta: The thermo physiological properties of the nonwoven fabrics were determined by using the Alambeta and Permetest instruments (Sensora Instruments, Czech Republic). The Alambeta instrument provides values for thermal conductivity, thermal resistance (insulation), thermal absorptivity (warmth-to-touch), fabric thickness and thermal diffusivity as shown in Figure 1. The test instrument was used to analyse the transient and steady state thermo physical properties of the fabrics. The specimens of 20cm×20cm were prepared and placed in between two plates. With the two plates the heat flow through the fabric due to the different temperature of the bottom measuring plate (at ambient temperature) and the top measuring plate which is heated to 40 ̊C. The thermal absorptivity of the textile structure is a measure of the amount of heat conducted away from structure’s surface per unit time (1). The test was performed on the dry and wet states of the nonwoven fabrics which were wetted with 0.2ml of distilled water in the centre of the fabrics and allowed 4 minutes before retesting, in order to allow for the thermal recovery of the fabric. All the tests were carried out on both faces of each specimen and the mean values were calculated.1,2

The use of conductive wires for smart and protective textiles

The aim of this study was to develop and evaluate conductive core wires reinforced cotton yarns for smart and protective textile applications. Different sensors will be attached to the developed textile structures and will employed in rehabilitation to give the patient an online feedback. The stainless steel (SS), copper (Cu) and silver treated copper (Cu/Ag) conductive wires at different diameters (40, 50 and 60 micron) were employed as the core of the Ne20 cotton yarns. A number of different yarns were produced with and without core wires. A conventional ring spinning system with an attachment was used to produce core yarns. The interaction between the yarn quality and the core wires were tested and analyzed. 20 copses of yarns were produced by using different yarn process combinations. The yarn properties were tested in terms of yarn count, yarn twist, yarn hairiness, breaking strength and elongation. As a result, the properties of cotton yarns were affected by the wire reinforcement. The tested parameters have changed in varied extents. The types of the conductive wires also had different effect on the core yarn properties.

Effect of ultrasonic laundering on thermophysiological properties of knitted fabrics

The paper focuses on the application of ultrasonic energy in textile laundering. In recent years, there has been an increasing interest in ultrasonic energy application in textile industry; however, the effect of ultrasonic laundering on the thermophysiological properties of knitted fabrics has not been studied yet. This study was conducted by using polylactic acid (PLA), cotton, polyethylene terephthalate (PET), and poly acrylic (PAC) fibres containing yarns and their blends. Knitted fabrics, single pique, were made from these yarns by using weft knitting machine. The fabrics were washed ten times for 15 and 60 minutes under 40 °C by using conventional and ultrasonic washing methods. The main aim was to determine the effect of washing methods on the thermophysiological properties of the fabrics. It is also aimed to analyse and evaluate the thermophysiological properties of the PLA fabrics. The incorporation of 100 % PLA and cotton/PLA yarns into single pique knitted fabrics has been attempted to produce for the first time and studied their thermal comfort properties. The results show that the washing processes have a critical importance for the tested fabrics in terms of thermal conductivity, thermal resistance, thermal absorbtivity, water vapour permeability, and heat loss. It has been also demonstrated that the fabric cleaning by using ultrasonic method enhanced the properties of tested fabrics such as thermal conductivity and % recovery. It was also noted that 15 minutes ultrasonically washed fabrics had significantly lower thermal resistance as compared to conventionally washed fabrics.