The influence of antimicrobial activity of two contemporary finishes, specifically a dispersion of colloidal silver (Ag) and 3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride (Si-QAC), on the degree of biodeterioration of 100% cotton (CO) fabric and fabric composed of a mixture of cotton and polyester (CO/PES) with the ratio 50:50 was studied. Ag was chosen for the leaching agent, while Si-QAC was used as the biobarrier-forming agent. The biodeterioration of samples finished with different concentrations of Ag and Si-QAC was analysed from a standard soil burial test after 3, 6 and 12 days of exposure to soil microflora. SEM micrographs revealed intensive biodeterioration of the unfinished cellulose fibres, while the highly biologically resistant polyester fibres remained undamaged. A controlled release of Ag successfully inhibited biodeterioration of the cellulose fibres in the CO and CO/PES fabrics when its concentration reached a lethal, biocidal concentration. Contrary to the effects of Ag, the biobarrier formation of Si-QAC on CO and CO/PES fabrics was insufficient to protect the cellulose fibres during longer periods of soil burial, irrespective of its concentration. Intensive chemical changes to the cellulose were clearly seen from the FT-IR spectra of all of the samples. The resistance of the polyester component to biodeterioration did not provide any significant protection for the cotton component in CO/PES fabric.
COBISS.SI-ID: 2556272
The possibility of incorporating a stimuli-responsive microgel into a silica matrix by the sol-gel method was studied. This method allows the preparation of a novel class of finishes for textile fibre modification, which enables the creation of simultaneous stimulus-responsive behaviour and functional protective properties. Using a pad-dry-cure method, a thermo- and pH-responsive microgel based on poly-(N-isopropylacrylamide) (poly-NiPAAm) and chitosan (PNCS microgel) was embedded into a silica matrix on a polyester (PES) fabric composed of a model sol-gel precursor, vinyltrimethoxysilane (VTMS), in combination with hydrophilic fumed silica nanoparticles (SiO2). Morphological and chemical properties of finished PES samples were characterised by using SEM, FT-IR and XPS analysis. The stimulus response of the PNCS microgel on the samples before and after five consecutive washings was established by measuring its porosity, wicking ability, moisture content, drying rate, water vapour transmission rate and water uptake. The results showed that sol-gel technology is an appropriate method for the deposition of PNCS microgel in PES fibres. Because of the elasticity of the sol-gel matrix, the VTMS/SiO2 polysiloxane film had no influence on the swelling/deswelling effect of the PNCS microgel, thus retaining its stimulus response.
COBISS.SI-ID: 2673776
The Langmuir-Blodgett (LB) method was used for depositing cubic polyhedral oligomeric silsesquioxanes (T8POSS) onto Au, indium tin oxide (ITO) and mica supports. Three different T8POSS were examined; two were amphiphilic and aggregated upon transfer to a solid support, while the highly symmetric POSS (termed MP8) gave stable and reproducible Langmuir films as studied by surface pressure and transfer ratio measurements. This was attributed to the eight identical alkanethiol groups located on each of the eight corners of the cubic like skeleton. The LB films were studied by RA-FTIR, XPS, contact angle and cyclic voltammetry. These techniques revealed the formation of a permeable, yet, stable layer. The symmetric MP8 was utilized as a bridging building block between the support and Au nanoparticles (Au-NPs). This assembly was examined by means of AFM, SEM and anodic oxidation of the nanoparticles. An average density of 1.45 * 109 nanoparticles cm-2 was obtained for the deposited Au-NPs on the MP8 layer. Furthermore, anodic stripping voltammetry was used for studying the extraction of Hg2+ by the MP8 LB film.
COBISS.SI-ID: 4783642