Tatjana V. Mihailovic

Some Properties of Antimicrobial Coated Knitted Textile Material Evaluation

The aim of this work was to investigate the antimicrobial activity of knitted fabric intended for medical purposes as well as the influence of antimicrobial treatment on the compression work, volume resistivity, water sorption. and water retention of the examined material. Polyamide/elastane plain jersey knitted fabric was treated with a polymer matrix of chitosan gel in which either gentamicin sulfate or autochthonous essential oil of Picea abies was incorporated as an active substance. The treated fabrics showed a wide range of antimicrobial activity on microorganisms (Staphilococcus aureus, Escherichia coli, Klebsiella and Candida albicans ) and therefore may have various medical applications. However, antimicrobial treatment changed the mechanical and physical-hygienic properties of the knitted fabric. The antimicrobial coatings decreased the total, elastic and irreversible compression work, water sorption, and volume resistivity, and increased the water retention of the fabrics. Antimicrobial treatment with chitosan and gentamicin sulfate produced a knitted fabric with good antimicrobial properties. However, if good mechanical and physical-hygienic properties are required, antimicrobial treatment with chitosan and essential oil of Picea abies has the advantage over treatment with gentamicin sulfate.

Investigation of fabric deformations under different loading conditions

The phenomenon of fabric deformation can be observed not only keeping in mind the type of material, the raw material, geometric and constructive parameters, but also the conditions which which material is exposed under action of tensile force (the size of force, time, velocity of acting and so on). Investigates the influence of the tensile force size on total deformation as well as the deformation components: elastic, viscoelastic and plastic. Reports an experiment conducted on clothing wool fabrics (18 different samples) which were exposed to various tensile forces (5, 10, 15, 20, 25, 30 and 35 per cent of breaking force) during 15 minutes. After this time limit had expired, their relaxation in a period of 24 hours was examined. From the diagrams of fabric relaxation (126 diagrams), determines deformation components and presents a summary using diagrams. On the basis of imposed analysis claims it can be stated that elastic deformation component predominates while no plastic deformation exists at lower values of tensile force.

Resistance to creasing of clothing wool fabrics

Examines the resistance to creasing of a group of clothing wool fabrics by measuring the crease recovery angle in a definite time interval. Determines the boundary zones of elastic, viscoelastic and plastic deformation component values as well as the relaxation velocity. Describes through results the behaviour of clothing wool fabrics in conditions to which they are exposed during wearing.

Assessment of Electrical Behavior of Non‐Woven Textile Materials

Non‐woven textile materials have been increasingly used for a variety of applications in industry and daily life. This imposes a need for the investigation of electrical properties in different conditions of their usage. In the scope of this investigation, electrical conductivity and dielectric properties such as relative dielectric permeability and dielectric loss tangent of various polyester non‐woven textile materials were determined. Experimental values of frequency were in the limits of 80 kHz to 2 MHz at relative environmental humidity of 30%. In addition, aimed at discovering the behaviour of investigated material from the aspect of electrical conductivity in various conditions of environmental humidity, the electrical conductance was measured both at 30% and 80% of relative environmental humidity in the electric periodic field at the frequency of 1 MHz. All measurements were realised at the temperature of 30° C. Obtained results showed that with the increase of frequency of electric periodic field electrical conductivity of tested samples increases, while the values of dielectric properties decrease. Furthermore, it was found that the increase of relative environmental humidity provokes the increase of electrical conductivity of tested non‐woven samples.Non‐woven textile materials have been increasingly used for a variety of applications in industry and daily life. This imposes a need for the investigation of electrical properties in different conditions of their usage. In the scope of this investigation, electrical conductivity and dielectric properties such as relative dielectric permeability and dielectric loss tangent of various polyester non‐woven textile materials were determined. Experimental values of frequency were in the limits of 80 kHz to 2 MHz at relative environmental humidity of 30%. In addition, aimed at discovering the behaviour of investigated material from the aspect of electrical conductivity in various conditions of environmental humidity, the electrical conductance was measured both at 30% and 80% of relative environmental humidity in the electric periodic field at the frequency of 1 MHz. All measurements were realised at the temperature of 30° C. Obtained results showed that with the increase of frequency of electric periodic field...

Multiaxial determination of the resistance to creasing of clothing wool fabrics

In this paper, values of deformation components (elastic, viscoelastic, plastic) of clothing wool fabrics by measuring the crease recovery angle in various directions to the warp direction (0°‐warp, 30°, 45°, 60°, and 90°‐weft) were determined. The size as well as the change of deformation component from warp to weft direction was presented through polar diagrams. On the basis of the results of investigation it is possible to conclude that all investigated fabrics (plain, 2/2 twill, cross twill), regardless of the biaxiality concerning quickly reversible (elastic) deformation, tend toward isotropy in total reversible deformation (elastic + viscoelastic). Concerning the plastic deformation value, mentioned investigated fabrics also express tendency toward isotropy.

Complex estimation of bending elasticity of hemp woven fabric after washing treatment

– This paper aims to investigate the elasticity of hemp woven fabric under action of bending force, before and after washing treatment., – Bending elasticity was monitored in three different ways: through the value of bending modulus, on the basis of fabrics resistance to creasing expressed through the value of quality number, and through the value of bending deformation components. On the basis of the results obtained from the mentioned three types of investigations, the complex criterion of quality of washed and unwashed hemp fabric, from the aspect of their elasticity, was formulated., – Values of complex criterion as well as the values of bending modulus, quality number and total recurrent deformation pointed to the conclusion that investigated hemp fabric has, not good, but satisfied bending elasticity, especially after washing treatment. The values of bending deformation components served for establishing Frenkels model of elastic behaviour under action of bending force of washed as well as unwashed hemp fabric., – Shows that the way on which Frenkels model was established might be interesting because of its simplicity., – Provides information on the elasticity of hemp woven fabric before and after washing.

Structural design of face fabrics and the core as a premise for compression behavior of 3D woven sandwich fabric

In this work, an experimental study on compression properties of two E-glass 3D woven fabrics, known as integrally woven sandwich fabrics, has been presented. Compression properties of 2D face fabrics and the core, as structural parts of integrally woven sandwich fabric, have also been investigated. Compression behavior of the samples (compressibility, compression work, and compressive resilience) was analyzed from the aspect of the weave design of face fabrics and the core structure (shape and density of the pile yarns). Results of the investigation showed that “8” shaped core structure, the greater surface density of the pile yarns, and the less compact structure of face fabrics ensure better compression properties of 3D fabrics. Specific weave design of face fabrics and the structure of the core significantly influence the behavior of 3D fabrics during successive increases, followed by a gradual decrease of pressure. During the loading of 3D woven structures, three regions of curves can clearly be seen compared to two regions which are registered at 2D face fabrics. Concerning 3D woven fabrics, the first region represents compression of the core, the second region is prolonged core compression and the third region refers to the simultaneous compression of pile yarns in the core and face fabrics. The density of pile yarns plays an important role in the region 1. In region 2, both the shape and density of the pile yarns are significant. Influence of the weave of face fabrics on compression behavior of 3D fabric can be noticed to a lesser extent in the region 2 and, especially in the region 3, where highly packed yarns assemblies are created.

Evaluation of the quality of clothing fabrics in terms of their compression behaviour before and after abrasion

In this work, the compression behaviour of clothing woven fabrics, before and after abrasion on the Martindale’s device, has been examined. Plain and 3/1 twill weave fabrics from cotton and cotton/polyester fiber blends served as experimental material. Compression behaviour of the investigated fabrics was analyzed taking the compressibility, thickness loss, and compressive resilience into consideration. Obtained results showed that the changes of compression properties are in a function of the structural parameters of tested fabrics, as well as damages caused by abrasion. Besides, the results of compressibility, thickness loss, and compressive resilience enabled establishing the quality of examined fabrics based on values of complex criterion. Calculated value of complex criterion pointed to the conclusion that abrasion causes the reduction of quality of tested fabrics in a small extent. Twill weave fabric made of cotton/polyester fiber blends is characterized by the best quality while cotton plain weave fabric has the worst quality, before as well as after abrasion.