A two-step antimicrobial finishing procedure was applied to woollen (WO) and polyester (PES) fabrics and a WO/PES fabric blend in which the pad-dry-cure method was performed to create a functional silica matrix through the application of an inorganic-organic hybrid sol-gel precursor (RB) followed by the in situ synthesis of AgCl particles on the RB-treated fibres using 0.10 and 0.50 mM AgNO3 and NaCl, respectively. The bulk concentration of Ag on the cotton fibres and the antimicrobial activity were determined. The results showed that the highest concentration of the adsorbed Ag compound particles was obtained on the WO samples followed by the WO/PES and PES samples. The antimicrobial activity of the finished fabric samples strongly depended not only on the amount of adsorbed Ag but also on the properties of the fabric samples. Whereas Ag biocidal activity was generated for the finished PES samples at Ag particle concentrations less than 10 mg/kg, the 34-times higher Ag particle concentration on the WO samples was insufficient to impart satisfactory antimicrobial activity because Ag chemically binds to the thiol groups on wool. The presence of wool fibres in WO/PES samples decreased the antimicrobial activity of the blend fabric compared with that of the PES fabric. A lethal concentration of adsorbed Ag compound particles for bacteria and fungi was produced only through the treatment of the WO and WO/PES samples with 0.5 mM AgNO3.
COBISS.SI-ID: 2896752
The feasibility of a complete enzymatic one-bath pre-treatment of the cotton fabric at low temperature was investigated in this study. The cotton fabric was enzymatically desized, scoured and bleached with an enzyme mixture of starch degrading enzymes, pectinases and glucose oxidases, respectively. Starch-degrading enzymes hydrolyzed the sizing agent into glucose. Enzymes glucose oxidases catalyzed the oxidation of β-D-glucose to D-glucono-δ-lactone and simultaneously generated hydrogen peroxide. The desizing and hydrogen peroxide generation took place for one hour at temperature of 50 °C in a slightly acid pH range. For bleaching, hydrogen peroxide was converted into peracetic acid by incorporating the bleach activator tetra acetyl ethylene diamine (TAED). Bleaching took place at 50 °C and neutral pH, where peracetic acid is most effective. Enzymes pectinases were added into the pre-treatment bath to remove pectins from fibers and improve their wettability. Whiteness values, water absorbency, polymerization degree and tenacity at maximum load were measured on pre-treated samples. The total organic carbon, pH and biodegradability were measured on residual pre-treatment baths. It was established that hydrogen peroxide can be efficiently enzymatically produced from the sizing agent and converted with TAED to form peracetic acid to bleach the cotton fabric. Cotton fabrics with a medium degree of whiteness, WI=51, and good water absorbency can be obtained at low water and energy consumption.
COBISS.SI-ID: 2776432
The aim of this study was to introduce a new non-formaldehyde inorganic-organic hybrid sol-gel flame-retardant precursor (SiOP) containing phosphorous, nitrogen, and silicon and to compare its functional properties with those of the conventional formaldehyde-containing organic flame-retardant agent, organophosphonate (OP). Both agents were applied to 100% cotton (CO) woven fabric by the pad-dry-cure method under the appropriate conditions at different concentrations. The presence of the SiOP and OP coatings on the CO fabric was confirmed by SEM, EDS and FTIR. The results of the vertical tests of flammability and the TG analyses showed that the presence of the SiOP coating changed the thermal degradation pathway of the CO fabric and resulted in an increase in the thermo-oxidative stability of the cellulose fibres. The thermo-oxidative stability was enhanced by the addition of higher amount of dry solids. At comparable dry solids contents, OP preserved significantly greater flame retardancy and thermo-oxidative stability than did SiOP. These results indicated that the SiOP precursor could not act as an effective alternative to the OP agent in the flame-retardant protection of CO fabric.
COBISS.SI-ID: 2918512
The aim of this research was to study the impact of material, knitted structure and relaxation process parameters on loop length. In addition, the objective was to examine the differences in loop length of single weft knitted fabrics, produced from different types of elasticized and non-elasticized yarns. For both groups of knitted fabrics, elasticized and non-elasticized, knitted fabric density and relaxation process influence the loop length most of all. Loop length decreases during the process of consolidation, but this decrease is not substantial. Addition of elastane does not significantly influence the loop length. Knowledge of all factors influencing loop length is vital for planning yarn consumption, comfort fit, quality, performance and aesthetic properties of knitted fabrics made from elasticized yarns.
COBISS.SI-ID: 2754928
In this research, a new two-step procedure of the surface modification was developed with the aim of creating the ''lotus effect'' on the cotton fabric surface. In the first step, the fibres were treated with the low-pressure water vapour plasma, followed by the application of a pad-dry-cure sol-gel coating with the water- and oil-repellent organic-inorganic hybrid precursor fluoroalkyl-functional siloxane (FAS). The tailored ''lotus effect'' was confirmed by measurements of the contact angle of water (154°) and n-hexadecane (140°), as well as by measurements of the water sliding angle (7°), which were used to identify the superhydrophobic, oleophobic and self-cleaning properties of the modified fibres. The results show that the plasma pretreatment simultaneously increased the surface polarity, roughness, and surface area of the fabric. The application of the FAS coating after plasma pretreatment caused a slight increase in the surface roughness, accompanied by a decrease in the surface area, indicating that the architecture of the surface was significantly changed. This result suggests that the surface pattern affected the ''lotus effect'' more than the average surface roughness. The plasma pretreatment increased the effective concentration of the FAS network on the fabric, which resulted in enhanced repellency before and after repetitive washing, compared with that of the FAS-coated fabric sample without the plasma pre-treatment.
COBISS.SI-ID: 2799984