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Influence of enzymatic pretreatment on colour of bleached and dyed flax fibres
Darinka Fakin, Vera Golob, Karin Stana-Kleinschek, 2006, izvirni znanstveni članek

Opis: In this paper the effect of enzymatic bioscouring on the bleaching and dyeing of flax fibres was studied in comparison with conventional alkaline scouring. Enzymatic bioscouring was performed with a commercial multi-enzyme system consisting of pectinases, hemicellulases and cellulases. The enzyme and alkaline scoured flax fibres were subsequently oxidatively bleached with hydrogen peroxide and dyed with direct dye C.I. Direct Red 80 under the same conditions. The efficiency of both the scouring and bleaching processes was evaluated by weight loss and the whiteness of the bleached samples was determined according to CIE formula. The exhaustion profile of the used dye was followed on-line during the dyeing process using absorbance measurement. The colours of bleached and dyed samples were evaluated using CIELAB colour values. The residual pretreatment and dyeing baths were ecologically analysed with COD, TOC and BOD5. The obtained results indicate that enzymatic scouring provides a lower weight loss, a higher degree of whiteness, comparable dyeing properties and is more environmentally friendly.
Ključne besede: textile fibres, flax, linen fibres, enzymatic pretreatment, dyeing, bleaching
Objavljeno: 31.05.2012; Ogledov: 853; Prenosov: 11
URL Povezava na celotno besedilo

The influence of thread twist on alterations in fibers` mechanucl properties
Andreja Rudolf, Jelka Geršak, 2006, izvirni znanstveni članek

Opis: In order to design high-quality threads, it is necessary to know the properties of threads and fibers, as well as the loadings and deformations which may occur during the sewing process. Thread properties depend on the mechanical properties of the fiber and the constructional parameters of the thread and its surface treatment, which directly influence sewing performance.The mechanical properties of a thread primarily depend on the fiber mechanical properties and the amount of twist. Knowledge of the thread dynamic loadings during the sewing process, depending on the number of turns and the lubrication method, is important for planning the required processing properties of the thread. This paper presents research into the influence of thread twist and the lubrication method on the mechanical properties and dynamic load of PES core-spun thread and its fibers. Research into the mechanical properties of the different twisted and surface treated threads, and separated fibers was carried out for this purpose. The influence of threaddynamic load during a sewing process was also researched regarding any alterations in the mechanical properties of the threads and separated fibers. Analyses of the results show that the amount of twist depends on the mechanical properties of the thread and its constituent fibers, whilst the method of surface treatment is based on the specific mechanical properties of the thread. A dynamic load causes greater or smaller thread deformations, which is reflected in changes in the thread and fiber mechanical properties. The occurred changes depend on dynamic load, amount of twist, and the lubrication method, which is confirmed with statistical analysis of the measured results.
Ključne besede: garment manufacturing, sewing, threads, textile fibres, surface treatment, dynamic loads, mechanical properties, amount of twist
Objavljeno: 30.05.2012; Ogledov: 1515; Prenosov: 18
URL Povezava na celotno besedilo

Study of crosslinking efficiency of cotton cellulose by different physical-chemical methods and genetic programming
Olivera Šauperl, Miran Brezočnik, 2006, izvirni znanstveni članek

Opis: We have investigated the crosslinking effect of unmercerized and mercerized cotton celluose crosslinked with different BTCA mass fractions in the impregnation bath. Crosslinking efficiency was analyzed using FT-IR spectroscopy, water retention capacity method, tensiometry and the methylene blue method. On the basis of the experimental data which was obtained with theseparate physical-chemical methods, different prediction models for crosslinking efficiency was developed. Modelling was taken out with the genetic programming method. Research shows good accordance of the experimentaldata with the genetic models.
Ključne besede: textile fibres, cotton, cellulose, crosslinking, FTIR spectroscopy, methylene blue method, water retention capacity, tensiometry, genetic programming
Objavljeno: 30.05.2012; Ogledov: 1255; Prenosov: 39
URL Povezava na celotno besedilo

Tyrosinase catalysed coupling of functional molecules onto protein fibres
Suzana Jus, Vanja Kokol, Georg M. Gübitz, 2008, izvirni znanstveni članek

Opis: Grafting, using oxidative enzymes shows a high potential for wool fibres funktionalisation. In this work we attempt to graft on wool fibres with phenolic antioxidants order to introduce and improve the properties of the fibre. The approach of tyrosinase to oxidize tyrosine residues in wool proteins to quinones, which can further react with free sulfhydryl (thiol), amino or phenolic groups of different substrates was exploited to couple different phenolic antioxidants (caffeic acid and chlorogenic acid) onto the wool fibre proteins. Tyrosinase catalysed reactions were followed by different analytical methods like oxygen consumption, FT-NIR Raman and UV/VIS spectroscopy. It was proved that phenolic compounds used are strongly cross-linked on the wool fibre resulting to an improved antioxidant activity.
Ključne besede: textile fibres, wool fibers, tyrosinase, caffeic acid, chlorogenic acid, grafting, chemical modification of fibres
Objavljeno: 31.05.2012; Ogledov: 933; Prenosov: 59
URL Povezava na celotno besedilo

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: 1260; Prenosov: 33
URL Povezava na celotno besedilo

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: 1297; Prenosov: 66
URL Povezava na celotno besedilo

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: 1114; Prenosov: 57
URL Povezava na celotno besedilo

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: 1145; Prenosov: 20
URL Povezava na celotno besedilo

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: 934; Prenosov: 53
URL Povezava na celotno besedilo

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: 1053; Prenosov: 66
URL Povezava na celotno besedilo

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