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1.
Hydrophilic/hydrophobic characteristics of different cellulose fibres monitored by tensiometry
Zdenka Peršin, Karin Stana-Kleinschek, Tatjana Kreže, 2002, izvirni znanstveni članek

Opis: Wettability and sorptivity improvements for different textile materials are the major tasks during textile finishing. In order to improve the sorption characteristics of a cellulose fabric, different pre-treatment processes are applied, usually washing, bleaching and mecerisation. Differences in the sorption properties of untreated and pretreated (washed and bleached) regenerated cellulose fibres were obtained using tensiometry and compared with the classical method for determining moisture adsorption. Results show that compared to raw fibres, viscose fibres have the highest moisture and the smallest contact angle whilst modal fibres have the biggest contact angle. Pretreatment increases the sorption abilities and makes the material more accessible to chemicals used in the finishing process. Using the conventional method, it can be confirmed that fibres with the highest moisture have the smallest contact angle (tensiometry).
Ključne besede: textile materials, regenerated cellulose fibres, sorption, pretreatment, tensiometry
Objavljeno: 05.07.2017; Ogledov: 579; Prenosov: 81
.pdf Celotno besedilo (137,76 KB)
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2.
Microvoid system in fibres
Majda Sfiligoj-Smole, Diana Gregor-Svetec, 2002, izvirni znanstveni članek

Opis: The macrovoid system of poly(ethylene terephthalate) (PET) and poly(propylene) (PP) fibres was studied by small-angle x-ray scattering (SAXS). Commercial PET textile fibres were treated in different media and the influence on fibre homogeneity was followd by SAXS. PP technical fibres were manufactured on a laboratory spin-drawing device and subsequently drawn at different drawing conditions on a laboratory drawing device. The influence of drawing on the pore system was followed.
Ključne besede: textile industry, textile fibres, morphology, structure, investigations, SAXS, poly(ethylene terephtalate), PET, poly(propylene), PP, voids, microvoids
Objavljeno: 10.07.2015; Ogledov: 780; Prenosov: 69
.pdf Celotno besedilo (284,24 KB)
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3.
Application of spectrophotometric methods in assessing the influence of alkaline treatment on the degree of crosslinking of cotton cellulose with BTCA
Olivera Šauperl, Karin Stana-Kleinschek, Bojana Vončina, Majda Sfiligoj-Smole, Alenka Majcen Le Marechal, 2003, izvirni znanstveni članek

Opis: Polycarboxylic acids appear to be the most promising nonformaldehyde crosslinking agents to replace the traditional, mostly formaldehyde-based, compounds. The most effective among these acids is 1,2,3,4-butanetetracarboxylic acid (BTCA). In this study, a comparison was made of the crosslinking effect on mercerized and on unmercerized as well as with different BTCA mass fractions crosslinked cotton fibres using FT-IR spectroscopy, the methylene blue method and water retention determination. The main purpose of the research was to evaluate how the structural changes of mercerized cotton (transformation of cellulose I into cellulose II) influence the crosslinking of cellulose fibres.
Ključne besede: textile fibres, cotton fibres, cotton cellulose, mercerization, crosslinking
Objavljeno: 01.06.2012; Ogledov: 1662; Prenosov: 98
.pdf Celotno besedilo (169,10 KB)
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4.
[Beta]-cyclodextrin as a retarding reagent in polyacrylonitrile dyeing
Bojana Vončina, Vera Vivod, Darja Jaušovec, 2007, izvirni znanstveni članek

Opis: ß-Cyclodextrin was tested as a dye complexing agent - as a dye retardant in the dyeing of PAN fibres with cationic dyes. Significant improvement of colouruniformity and some improvements in colour depth were observed when PAN fibres were dyed in the presence of ß-cyclodextrin as compared to dyeing in the presence of a commercial retardant.
Ključne besede: textile dyeing, cationic dyes, cyclodextrin, polyacrylonitrile fibres, complexation
Objavljeno: 01.06.2012; Ogledov: 1354; Prenosov: 17
URL Povezava na celotno besedilo

5.
Topochemical modification of cotton fibres with carboxymethyl cellulose
Lidija Fras Zemljič, Peer Stenius, Janne Laine, Karin Stana-Kleinschek, 2008, izvirni znanstveni članek

Opis: The research reported in this paper demonstrates that the capacity of cotton fibres to adsorb cationic surfactants as well as the rate of the adsorption process can be increased by adsorbing carboxymethyl cellulose (CMC) onto the fibre surfaces; in addition, the adsorption can be restricted to the fibre surface. CMC was deposited by means of adsorption from an aqueous solution. The adsorption of N-cetylpyridinium chloride (CPC) from an aqueous solution onto the CMC-modified fibres was measured using UVspectrometric determination of the surfactant concentration in the solution. Adsorption onto the cotton fibres was studied in a weakly basic environment (pH 8.5) where cotton fibres are negatively charged and the CPC ion is positively charged. Modification of the fibres by adsorption of CMC introduces new carboxyl groups onto the fibre surfaces, thereby increasing the adsorption capacity of the fibres for CPC. The initial rate of adsorption of CPC increased proportionally with the amountof charge; however, this rate slowed down at high degrees of coverage onfibres with a high charge. The adsorption of cationic surfactant to the anionic surface groups was stoichiometric, with no indication of multilayer oradmicelle formation. It was evident that the acidic group content of the fibres was the primary factor determining cationic surfactant adsorption to these fibres.
Ključne besede: textile fibres, cotton fibres, modification, carboxymethyl cellulose, acid groups, charge increase, conductiometric titration, phenol-sulphuric acid test, practical applications
Objavljeno: 01.06.2012; Ogledov: 1412; Prenosov: 87
URL Povezava na celotno besedilo

6.
Tyrosinase-catalysed coating of wool fibres with different protein-based biomaterials
Suzana Jus, Vanja Kokol, Georg M. Gübitz, 2009, izvirni znanstveni članek

Opis: The potential of tyrosinases to activate tyrosine residues of wool protein fibres for cross-linking with different materials like collagen, elastin and gelatine was assessed. Natural fibres like wool offer an excellent environment for the growth of micro-organisms when the conditions like moisture, oxygen and temperature are appropriate. Coating with collagen, a very useful biomaterial with bactericidal and fungicidal properties, could be used to improve the properties of wool-based materials, especially when applied in hygienically sensitive applications like in hospitals. Tyrosinases were shown to catalyse the oxidation of tyrosine residues in wool and wool hydrolysates as model substrates, as determined by UV-Vis spectroscopy. Structural differences of the surface were evident from the increase of the intensity in the NH bending and stretching regions in the spectra of NIR FT Raman analysis of the enzyme treated and grafted wool fibres. The durability of the coating was also shown by using FITC-labelled collagen that was bound to the wool fibres, even after severe washing. Additionally, antimicrobial properties were successfully imparted due to the collagen grafted on the wool fibres. The functional and mechanical properties of the treated wool fibres showed no significant changes.
Ključne besede: textile fibres, wool, protein substrates, tyrosinase, enzymatic coupling, antimicrobial properties, coating
Objavljeno: 01.06.2012; Ogledov: 1256; Prenosov: 73
URL Povezava na celotno besedilo

7.
Flax fibres sorption properties influenced by different pretreatment processes
Tatjana Kreže, Severina Iskrač, Majda Sfiligoj-Smole, Karin Stana-Kleinschek, Simona Strnad, Darinka Fakin, 2005, izvirni znanstveni članek

Opis: The sorption behavior of raw and treated flax fibers was investigated. This paper presents the effect of conventional pretreatment processes (alkaline, acid) in comparison to environment-friendly enzymatic processes on the sorption ability of flax fibers. Weight-loss, moisture sorption, water retention value and contact angle were determined in order to interpret the pretreatment results. In addition, the influence of the process on the fibers' mechanical properties was studied. The ecological parameters of the treatment wastewaters were analyzed.
Ključne besede: textile fibres, flax, flax fibre properties, pretreatments, sorption properties, mechanical properties, ecological parameters
Objavljeno: 01.06.2012; Ogledov: 1567; Prenosov: 27
URL Povezava na celotno besedilo

8.
Characterisation of grass fibres
Majda Sfiligoj-Smole, Tatjana Kreže, Simona Strnad, Karin Stana-Kleinschek, Silvo Hribernik, 2005, izvirni znanstveni članek

Opis: The elementary grass fibres were isolated from different grass and legumes sorts, i.e. Ryegrass (Lolium hybridum Gumpenstein), Wheat straw, Trefoil (Trifolium pratense) and Lucerne (Medicago sativa). The fibre-samples were obtained in a bio-refinery, after the liquid phase containing proteins and lactic acid was eliminated from the ensiled and green grasses, respectively. For the isolation of elementary grass fibres different processes were used. The morphological characteristics of stems and leaves of different grass species were microscopically observed. On the microscopical stem and leaves cross-section samples the quantification of fibres sclerenchyma cells was performed. The quantitative analysis was carried out in order to obtain basic quantitative data on grass fibres, such as area of the single fibre or group of fibres, diameter of a single fibre or group of fibres and distances betweenthe most distant and least distant points on the area of the fibre. Measurements were made using a Carl Zeiss software KS 300, which runs on a computer connected to the image analysis equipment consisting of a microscope and a digital camera. In addition to, geometrical and mechanical properties ofisolated fibres and fibre bundles were determined. Due to the grass history,i.e. deformations and damages caused by the treatment of grasses in the bio-refinery, maturity grade, grass or legumes type and conditions during grass growth, the plant structures vary considerable in their properties.
Ključne besede: textile fibres, plant fibres, grass, properties
Objavljeno: 01.06.2012; Ogledov: 1451; Prenosov: 83
URL Povezava na celotno besedilo

9.
Analysis of the oxidation of cellulose fibres by titration and XPS
Lidija Fras Zemljič, Leena Sisko Johansson, Peer Stenius, Janne Laine, Karin Stana-Kleinschek, Volker Ribitsch, 2005, izvirni znanstveni članek

Opis: The purpose of this study was to evaluate the effect of selective oxidation on the surface properties of cotton cellulose fibres. Four different methods to evaluate the accessibility, nature and content of ionisable acidic groups (charge) in the fibres were applied: potentiometric and conductometric titrations, polyelectrolyte adsorption and X-ray photoelectron spectroscopy (XPS). The results from this combination of methods show that two processes take place when the oxidation method is applied: elimination of low molecular mass non-cellulosic compounds and formation of new acidic groups in the cellulose chains. Which of these processes is predominating depends on oxidation time, but the first one is initially more important. Polyelectrolyte adsorption and XPS show that the surface concentration of acidic groups is considerably lower than the bulk concentration, i.e. during oxidation the content of carboxyl groups in the surface region decreases, while it increases in amorphous regions. The decrease is due to the dissolution of low molecular weight compounds; the increase is due to the formation of new acidic groups. The use of titration methods in combination with XPS appears to be a very useful tool for identification of the formation and distribution of ionic groups in cotton fibres and their surfaces.
Ključne besede: textile fibres, cotton fibres, cellulose fibres, oxidation, X-ray photoelectron spectroscopy, XPS, acid groups in fibres
Objavljeno: 01.06.2012; Ogledov: 1699; Prenosov: 96
URL Povezava na celotno besedilo

10.
Grafting of cotton with [beta]-cyclodextrin via poly(carboxylic acid)
Bojana Vončina, Alenka Majcen Le Marechal, 2005, izvirni znanstveni članek

Opis: Cyclodextrins are cyclic oligosaccharides. Cyclodextrin molecules can form inclusion complexes with a large number of organic molecules. The properties of cyclodextrins enable them to be used in a variety of different textile applications. Cyclodextrins can act as auxiliaries in washing and dyeing processes, and they can also be fixed onto different fiber surfaces. Because of the complexing abilities of cyclodextrins, textiles with new functional properties can be prepared. Poly(carboxylic acid)s such as 1,2,3,4-butane tetracarboxylic acid (BTCA) are well-known non-formaldehyde crosslinking reagents. BTCA has four carboxylic acid groups, which can react with hydroxyl groups of cellulose and form stable ester bonds. We crosslinked -cyclodextrin molecules on hydroxyl groups of cellulose via BTCA.
Ključne besede: textile fibres, chemical modification, beta cyclodextrines, butane tetracarboxylic acid, BTCA, FTIR, host-guest systems, formaldehyde-free crosslinking reagents
Objavljeno: 01.06.2012; Ogledov: 1612; Prenosov: 45
URL Povezava na celotno besedilo

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