Marija Gorenšek

Nanosilver Functionalized Cotton Fabric

The influence of reactive dyes with massive chromogene and nanosilver on ultraviolet protective factor (UPF) values of lightweight cotton fabrics was investigated. The effect of nanosilver on the color of cotton fabrics and on antibacterial effectiveness was also determined. AATCC Test method 183-1998 was used for the calculation of the UPF of lightweight cotton fabric. The antibacterial activity was determined according to ASTM Designation E 2149-01. The research shows an increase in the UPF values of lightweight cotton fabrics when they are pale red or pale navy dyed with nanosilver. Cotton fabrics treated with 80 nm nanosilver showed inhibition of the growth of Streptococcus faecalis and Staphylococcus aureus. Changes of color are observed on dyed cotton fabrics treated with nanosilver.

Functionalization of PET fabrics by corona and nano silver

In this work, the antibacterial and other properties of polyester fabrics previously functionalized by corona and/or silver nano particles have been studied. Corona air plasma was used as a pretreatment of raw, washed and washed-thermostabilized polyester fabrics to increase the adhesion of nano silver particles resulting in an excellent antibacterial effect. X-ray photoelectron spectroscopy was applied to analyze the surface composition and chemical bonding of the surface atoms on untreated and treated fabrics. The surface morphological changes of polyester fibers were observed by scanning electron microscopy (SEM). The quantity of silver on the polyester fabrics was determined by the use of the inductively coupled plasma-atomic emission spectrometry method. The antimicrobial properties of functionalized polyester fabrics were tested according to American Society for Testing and Materials ASTM Designation: E 2149-01. Additionally, the dyeing of polyester fabrics with selected disperse dye as well as capillary action tests were performed to confirm the chemical and morphological changes of polyester fibers after corona treatment. Considerable differences in surface composition were found between the raw and washed or washed-thermostabilized fabrics. The surface of raw fabrics is richer in carbon and the concentrations of the C—O and O—C=O groups are lower than on the other samples. An opposite effect is observed for washed and washed thermostabilized fabrics. SEM analyses show that the plasma treatment also affects the surface morphology. The chemical surface composition and morphology are highly related to the hydrophobicity and hydrophylicity, and the achievement of better nano silver adhesion and enhanced dyeing and antimicrobial properties of differently prepared corona plasma-treated polyester fabrics. Therefore, corona air-treated raw polyester fabrics demonstrated optimum antimicrobial properties due to the excellent adhesion of nano silver.

CF4 plasma and silver functionalized cotton

In an attempt to use minimal concentrations, initially, of silver nanoparticles for loading onto textiles and to achieve maximum concentrations on the material, CF4 low-pressure plasma was used on bleached and mercerized cotton fabric. The concentrations of silver on the fabrics were determined by the ICP-MS method (inductively coupled plasma-mass spectrometry), the morphology of fiber surfaces was observed with a scanning electron microscope (SEM), and an x-ray photoelectron spectroscopy (XPS) study was used for the evaluation of surface chemical changes. The antibacterial effect of silver loaded fabrics was tested against Enterococcus faecalis and Pseudomonas aeruginosa. The best results were found for plasma-treated cotton fabric functionalized with 30 nm silver particles. The results show effective plasma etching of the fabric surface, which caused excellent adhesion of silver particles. Color measurements of dyed samples showed that CF 4 plasma does not affect the color of dyed cotton. The mechanical properties of cotton remain unaltered after plasma treatment.

Modifying the UV Blocking Effect of Polyester Fabric

The influence of conventional acid and alkaline high temperature dyeing procedures on fabric construction is investigated. The effects of weave construction, orange, red, and blue disperse dyes, double layers of fabrics, and UV absorber on the ultraviolet protection factors (UPF) of polyester fabrics are the topics of this research. A spectrophotometer with an integrating sphere is used to measure the uv transmittance of polyester fabrics according to an AATCC test. Small differences in the weight of fabrics after blind dyeing procedures already influence the uv transmittance of fabrics. Pale orange and blue dyed fabrics show a high enough UPF, while a pale red dyed fabric does not reach such values. Deep dyed and double layered fabrics and fabrics aftertreated with a UV absorber reach high UPF values.

Functionalization of Polyester Fabric by Ar/N2 Plasma and Silver

The objective of this research was to use Ar/N2 (50%:50%) plasma to increase the adhesion of nano silver particles to raw polyester fabric. RUCO-BAC AGP was applied using the exhaust method. X-ray photoelectron spectroscopy revealed differences in surface composition between the Ar/N2 plasma-treated and untreated raw fabrics. The Ar/N2 plasma treatment was found to increase the surface carbon concentration and decrease the concentration of C-O and O-C=O groups on the surface. After plasma etching, the specific surface of the polyester fabric and properties related to it were found to change significantly. This change was confirmed by a decrease in the whiteness index and an increase in the dyeability of the polyester fabric with disperse dye. Morphological changes in the surface of plasma-treated polyester fabric enabled greater adhesion of nano silver particles and increased the antimicrobial effect with respect to Pseudomonas aeruginosa, Escherichia coli and Streptococcus faecalis.

The Influence of Water Vapor Plasma Treatment on Specific Properties of Bleached and Mercerized Cotton Fabric

The influence of water vapor plasma on chemical, morphological and mechanical properties of bleached and mercerized cotton fabric was studied. Reactive exhaust dyeing was used for loading of nano silver. Inductively coupled plasma mass spectroscopy results show that plasma treatment enhanced nano silver adhesion to the fabric, which also contributed to antimicrobial effectiveness to Pseudomonas aeruginosa and Escherichia coli. Surface changes of plasma treated cotton were observed with scanning electron microscopy. Xray photoelectron spectroscopy results show the decrease of C—C bonds in favor of C—O, O—C—O, C=O, and O=C—O bonds and higher O/C atomic ratio in plasma treated fibers. Mechanical properties of cotton yarn after plasma treatment remained unchanged.

Reactive Dyes and Nano-Silver on PA6 Micro Knitted Goods

The goal of our research was to obtain uniformly dyed PA6 micro knitted goods with excellent wet fastness, good UPF, and antibacterial properties. Newly developed reactive dyes and 80 nm silver particles were used. The AATCC-Test method 183 was used for the calculation of UPF of PA6 micro knitting. ICP-AES analysis was used for the determination of silver. Antibacterial activity of nano-silver on PA6 knitted goods was determined according to ASTM Designation E 2149-01. The research showed uniformly dyed PA6 micro knitting with excellent wet fastness. Dyed PA6 micro reached a UPF range between 15 and 24. ICP-AES showed high absorbance of silver. PA6 micro knittings treated with 80 nm nano-silver have high antimicrobial effectiveness against Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus, but after 10 washings the property is lost. Changes of color were observed on dyed PA6 micro knitting treated with nano-silver.

Parameters Influencing Dyeability of Cotton Warp at Dip-Dyeing for Jeans

The purpose of this research was to determine the influence of temperature, pH, and the addition of sodium oxide silicium oxide (soso) on the dyeability of cotton warp during the process of dip-dyeing. A simulation of the dip-dyeing technique was used. The results show a negligible influence of dip-dyeing bath temperature on the color yield of cotton warp. Lower pH values of dip-dyeing baths cause better dyeability. Addition of soso has a particular influence on the color yield of cotton warp. As a result, the dip-dyeing procedure is shortened when soso is used. The change of color of dip-dyed cotton warp, depending on different pH of the baths and on the addition of soso, was studied using x-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses. XRD showed that the dyeing conditions do not affect the crystallographic form of indigo, which is form B in all cases. On the other hand, SEM revealed the reasons for the observed effects in the differences in the morphology of the indigo crystallites.

The Influence of Stabilization under Various Conditions and Subsequent Treatment of Polyester Fabric on the Quantity and Composition of Extracted Oligomers

The study examined the effect of stabilization under various conditions (temperature, time and tension) and the treatment of polyester fabric in buffered solution (pH 12) prior to high-temperature dyeing, on the migration of oligomers. The content of oligomers in the treated polyester fabric was determined by extraction in petroleum ether and dichloromethane. The extract was analyzed using gel permeation chromatography (GPC). Based on the results it was established that oligomer migration was affected by temperature, time, and the stabilization tension. The greatest reduction in the content of oligomers was in polyester fabric that was stabilized in a restricted state at higher temperatures and longer times (220°C, 600 seconds). The oligomer content decreased even further if the polyester fabric was alkaline pre-treated. The GPC chromatograms showed that all oligomeric extracts consisted mainly of cyclic trimers, whereas the presence and proportion of other cyclic oligomers varied with treatment conditions.

The Influence of Treatment Conditions on the Quantity and Composition of Oligomers Extracted from Polyester Fabric

We investigate the influence of treatment conditions of polyester (PES) fabric on the quantity of extracted oligomers and their composition. Oligomers are extracted by petroleum ether and dichloromethane. The quantities of oligomers from the treated and untreated fabrics are determined gravimetrically, whereas the composition of the oligo meric extract is determined by gel permeation chromatography (GPC). The quantity of extracted oligomers decreases with alkaline pretreatment prior to acid dyeing or with an alkaline dyeing process. GPC chromatograms show that all oligomeric extracts consist mainly of cyclic trimers. The treatment conditions of PES fabric have only a slight influence on the breaking stress and elongation of the fabric. Alkaline pretreatment before acid and alkaline dyeings of PES fabric greatly decreases overall flexural rigidity compared with acid dyed fabric.