Browsing by Author "Wiener, Jakub"

Now showing 1 - 20 of 96
  • Thumbnail Image
    Item
    Aplikace a identifikace přírodních barviv pro účely restaurování textilií
    (Technická Univerzita v Liberci, 2007-01-01) Svobodová, Markéta; Wiener, Jakub
    The aim of the bachelor thesis is application and identification natural dyes on woolen and polyamid materials. Used dyes are made from plants wild madder color sense (Rubia tinctorum), cutcuma. Material was preliminary treatmented, colored and again modified to final form. Then due to infrared spectrometry and other methods for structure charekteristic and analytic identification was material analyzed. The results facillitate anallizing unknown dyes and can be for restoring needs.
  • Thumbnail Image
    Item
    Aplikace nanočástic stříbra na textilní substráty
    (Technická Univerzita v Liberci, 2010-01-01) Bizubová, Bibiána; Wiener, Jakub
    Cílem této diplomové práce je příprava nanočástic stříbra elektrochemickou metodou. V teoretické části práce jsou popsané současné poznatky o nanočásticích stříbra a jejich antimikrobiálních účincích. V experimentální části jsme analyzovali roztoky a taktéž materiály na kterých byli roztoky nanesené. Roztoky s nanočásticemi byli analyzované na laserovém analyzátoru velikosti částic, byla přeměřená spektrální charakteristika. Roztoky byli přeměřené na emisním spektrometru. Na připravených vzorcích byla testována změna barevnosti, antimikrobiální účinek, laserová spektroskopie. Vzorky byli snímané rastrovým elektronovým mikroskopem (REM).
  • Thumbnail Image
    Item
    Barevnost polyamidových vláken s ohledem na parametry vláken a textilií
    (Technická Univerzita v Liberci, 2010-01-01) Schmidtová, Markéta; Wiener, Jakub
    This Bachelor work deals with influence of fibre parameters and textile parameters on colourfulness of polyamide fibre. The theoretical part acquaints you with polyamide fibers, then apprises you which parameters could have some effect on resultant colourfulness. The experimental part describes process of experiment, whereat were the samples of various polyamide textile dyed, compares theirs colourfulness and evaluates influence of parameters on resultant values
  • Thumbnail Image
    Item
    Barvení různě jemných vlněných vláken kyselými barvivy
    (Technická Univerzita v Liberci, 2007-01-01) Chvalinová, Radka; Wiener, Jakub
    V diplomové práci byl sledován a hodnocen vliv jemnosti vlněných vláken při barvení. Vlněná vlákna různých jemností byla izotermně obarvena silně kyselým a slabě kyselým barvivem. Byla sledována kinetika sorpce barviv do vlákna v čase 5, 15 a 60 minut při teplotě 40°C, 60°C a 80°C. Byly stanoveny rychlostní konstanta K, rovnovážná koncentrace barviva ve vlákně C{$\infty$} a aktivační energie Ea. U všech vzorků byla sledována barevnost. Byl sledován vliv egalizačního prostředku slabě katonického charakteru při barvení vlny. Vliv katonického egalizačního prostředku byl hodnocen porovnáním kinetických veličin a K/S hodnot získaných z experimentálních dat barvení vlny slabě kyselým barvivem s daným egalizátorem a bez jeho přítomnosti. Pomocí obrazové analýzy byla sledována rovnoměrnost vybarvení v elementárních vláken. Tato nová metoda byla v této práci nazvána - mikroegalita. Tato metoda byla také použita pro vyhodnocení vlivu egalizačního prostředku v barvící lázni.
  • Thumbnail Image
    Item
    Barvení textilií II
    (2011-01-01) Kryštůfek, Jiří; Wiener, Jakub; Machaňová, Dagmar
  • Thumbnail Image
    Item
    Bio-Composites Reinforced with Natural Fibers: Comparative Analysis of Thermal, Static and Dynamic-Mechanical Properties
    (KOREAN FIBER SOC, KOREA SCIENCE TECHNOLOGY CTR #501 635-4 YEOGSAM-DONG, KANGNAM-GU, SEOUL 135-703, SOUTH KOREA, 2020-03-01) Mishra, Rajesh; Wiener, Jakub; Militký, Jiří; Petrů, Michal; Tomková, Blanka; Novotná, Jana
    In the present study, flax, jute and glass woven fabric samples were developed as reinforcement for composites with bio-epoxy resin. Flax fabrics were developed with plain weave, twill weave (different areal densities) and unidirectional (UD) structure. Jute fabrics were woven with three different structures i.e. plain, matt and twill respectively. For comparison purpose, glass woven fabric with plain weave and 3D orthogonal weave were used in this study. Static mechanical properties like flexural strength and impact resistance were studied. Dynamic mechanical properties were investigated by DMA 40XT RMI equipment.. Thermal conductivity has been studied for all composite samples. It is observed that the static mechanical properties of glass fabrics reinforced composites are superior but the flax & jute fabric reinforced composites are more flexible. The specific flexural strength as well as specific impact strength of the flax & jute fabric reinforced composites are competitive. The dynamic mechanical properties are comparable to that of glass fabric reinforced composites. They can be used in relatively lower load bearing applications as they are a sustainable source of materials for bio-composites which reduce the environmental burden and reduce the manufacturing cost.
  • Thumbnail Image
    Item
    Biocidní test pro textilní substráty
    (Technická Univerzita v Liberci, 2009-01-01) Vejsadová, Lenka; Wiener, Jakub
    Cílem bakalářské práce je výzkum biocidních vlastností komerčních antimikrobiálních prostředků v roztocích na bázi modelových organismů. Teoretická část je zaměřena na vlastnosti mikroorganismů, především na bakterie a modelové organismy. Podrobně jsou teoreticky zkoumány principy fermentace, vliv nanočástic stříbra a biocidních látek na modelové organismy a s tím související následné antibakteriální úpravy textilií. Experimentální část bezprostředně navazuje na teoretický výzkum. Modelové organismy v roztoku, či na nanesených textiliích se testují a vyhodnocují podle antibakteriálního a biocidního působení. Rovněž jsou tyto roztoky porovnávány s koloidním roztokem stříbra.
  • Thumbnail Image
    Item
    Cationization of cellulose fibers for composites
    (2017-01-04) Maqsood, Hafiz Shahzad; Bashir, Uzma; Zubair, Muhammad; Wiener, Jakub; Militký, Jiří
    In this work, composites were made by improved bonding of the cationized cellulosic fabric and some anionic matrix like Carboxymethyl Cellulose (CMC). Mercerized cotton fabric was cationized using cationization agent, TEXAMIN ECE with varying percentage from 1 to 10%. Those cationized cotton samples were incorporated in anionic matrices and the resultant composites were tested for mechanical properties on Universal Textile Tensile Testing machine. In the case of CMC as the matrix for the cationized reinforcement, the increasing trend in the tensile strength and elongation at break was observed. Scanning Electron Microscope images showed no extraordinary changes in the physical appearance of the cationized samples. Thermograms derived from Differential Scanning Calorimetry were informative for the evaluation of the thermal behavior of composites. © 2016 The Textile Institute
  • Thumbnail Image
    Item
    Chemická analýza textilií po plazmatické úpravě
    (Technická Univerzita v Liberci, 2009-01-01) Chládová, Andrea; Wiener, Jakub
    Tématem diplomové práce bylo provést pomocí atmosférického plazmatu modifikaci celulózových vláken, se zaměřením na sledování změn aldehydických a karboxylových skupin chemickou analýzou. Jako zdroj plazmy byl využit koplanární povrchový bariérový výboj DCSBD. Detekce funkčních skupin po plazmatické úpravě bavlny byla ověřena pomocí měďného čísla a speciálních barvících testů. Dále byla sledována možnost nahrazení vyvářky a odšlichtování při předúpravě bavlny plazmatickou modifikací, kdy pro analýzu a porovnání klasické a testované metody (plazmatická úprava) bylo použito smáčecího testu, stanovení sací výšky a barvení přímým barvivem. Byla využita i možnost detekovat míru modifikace plazmatem na neceulózových vláknech, konkrétně na polyesteru. Vyzkoušeno bylo stanovení měďného čísla využívajícího se pro stanovení míry poškození bavlny a dále barvící test s použitím kationtového barviva.
  • Thumbnail Image
    Item
    Chování PAL ve vlákenných soustavách
    (Technická Univerzita v Liberci, 2008-01-01) Špaldová, Miroslava; Wiener, Jakub
    Cílem bakalářské práce teoretické a experimentální části bylo stanovit povrchově napětí kapalin povrchově aktivních látek (PAL) v závislosti na jejich koncentracií a čase při jejich sorpci na použitý polymerní materiál (polypropylen, polyester). Dalším cílem bylo měření kontaktních uhlů roztoků povrchově aktivních látek, za účelem zjištění smáčevosti kapek povrchově aktivních látek na polypropylenových a polyesterových folií a následně zjistit povrchoví energii polypropylenové a polyesterové folii. V závěre této práce byly vyhodnocené výsledky jednotlivých měření experimentální části, které byly naměřené za pomoci přístrojů tenzometru Krüss K12 a Lucie.
  • Thumbnail Image
    Item
    Compression resilience and impact resistance of fiber-reinforced sandwich composites
    (2019-01-01) Mishra, Rajesh; Wiener, Jakub; Militký, Jiří; Petrů, Michal; Tomková, Blanka; Novotná, Jana
    This paper presents an experimental investigation on the compression behavior of fiber-reinforced sandwich composites. In this study, five different types of sandwich composites were prepared with warp knitted spacer fabric as middle layer. Four different types of woven Kevlar fabric structures were used as outer layers (skin) along with one sample of woven basalt fabric. The middle layer used is 100% polyester spacer fabric. Sandwich composites were fabricated using epoxy resin by wet lay-up method under vacuum bagging technique. Compression behavior, ball burst, and knife penetration were tested for all samples. The effect of outer layer of these composites on the mechanical performance was studied using the compression stress-strain curves. It is known that spacers have excellent compression elasticity and cushioning. Maximum knife penetration resistance is obtained with twill weave on surface because of maximum yarn cohesion and resin impregnation. Higher amount of cohesive friction results in higher resistance against penetration of sharp objects like the knife edge. Plain and twill fabrics offer sufficient resistance again ball burst. The yarn deformation allows formation of dome shape after ball impact. Maximum impact resistance in ball burst is obtained for plain weave because of highest level of interyarn binding. The results provide new understanding of knitted spacer fabric-based sandwich composites under compression and impact loading condition.
  • Thumbnail Image
    Item
    Dyeing, Fastness, and UV Protection Properties of Silk and Wool Fabrics Dyed with Eucalyptus Leaf Extract by the Exhaustion Process
    (Inst Chemical Fibres, 2011-01-01) Mongkholrattanasit, Rattanaphol; Kryštůfek, Jiří; Wiener, Jakub; Viková, Martina
    This research was concerned with dye extraction from the leaves of eucalyptus and with the application of this dye for silk and wool fabric dyeing by the exhaustion process. Optimal results were achieved when dyeing at 90 degrees C for 40 minutes and at pH 4. Silk and wool fabrics dyed in a solution composed of eucalyptus extract from leaves in combination with a mordant compound showed a shade of yellowish-brown. An exception was when the fabrics were dyed with FeSO4 mordant, resulting in a shade of dark grayish-brown. The colour fastness to light and rubbing after dyeing the silk and wool fabrics treated with the mordant was investigated, the results of which showed fair to good fastness, whereas the colour fastness to washing was at a good to very good level. The results confirmed that natural dyes from eucalyptus leaf extract have potential applications for fabric dyeing and producing ultraviolet (UV) protective silk and wool fabrics.
  • Thumbnail Image
    Item
    Effect of Hexamethyldisiloxane (HMDSO)/Nitrogen Plasma Polymerisation on the Anti Felting and Dyeability of Wool Fabric
    (Inst Chemical Fibres, 2014-01-01) Shahidi, Sheila; Ghoranneviss, Mahmood; Wiener, Jakub; Moazzenchi, Bahareh; Mortazavi, Hamideh
    This work is focused on the characterisation of the physical and surface properties of plasma coated wool fabric. A thin film was deposited on wool fabric samples by means of the plasma polymerisation of hexamethyldisiloxane (HMDSO) and differences between such plasma-treated and untreated fabrics were evaluated. The films deposited were characterised by means of Fourier transform infrared (FTIR) spectroscopy. Also the surface morphology of samples was studied using a scanning electron microscope (SEM). Hydrophobic properties of the samples were tested using the water drop test. The results show that by plasma polymerisation, hydrophobic properties of the wool surface change to super hydrophobic. The main aim of the HMDSO/N2 plasma polymerisation of wool fabrics is to improve anti felting properties and dyeing behaviour.
  • Thumbnail Image
    Item
    Effect of surface modification and knife penetration angle on the Quasi-Static Knife Penetration Resistance of para-aramid fabrics
    (2019-04-03) Javaid, Muhammad Usman; Militky, Jiri; Wiener, Jakub; Jabbar, Abdul; Salacova, Jana; Umair, Muhammad
    The focus of this paper is to describe the effect of change in surface friction of single layer para-aramid (TwaronA (R)) square woven fabric and change in knife penetration angle on its Quasi-Static Knife Penetration Resistance (QSKPR). The surface friction of fabric was changed by depositing SiO2 on its surface by using water glass as a precursor. Six different knife penetration angles (0 degrees, 22.5 degrees, 45 degrees, 67.5 degrees, 90 degrees and 135 degrees) were selected. Untreated and treated fabric samples were compared for change in QSKPR. It was observed that the deposition of SiO2 on the surface of TwaronA (R) fabric increased the surface friction which resulted in the increase in QSKPR. The response of fabric against QSKPR changed from partial yarn cutting to individual yarn cutting in fewer steps and load was distributed to a larger area due to decrease in yarn slippage. The change in penetration angle changed the distance, knife cutting edge travelled to cut each next yarn(s) and when this distance increased, the QSKPR was reduced. The post-penetration image analysis of damaged fibres showed that the load distribution among warp and weft yarns was complementary and change in penetration angles changed the distribution of stabbing load among the warp and weft yarns. When yarns with higher tensile strength and less slippage were loaded, the fabric showed highest resistance to penetration. A QSKPR prediction model was also proposed at the end.
  • Thumbnail Image
    Item
    Effects of temperature on sorption process using nanofibrous membrane
    (Technická Univerzita v Liberci, 2012-01-01) Ngcobo, Paul Sicelo; Wiener, Jakub
    The release of dyes into the environment only contributes a small proportion of water pollution but due to dye brilliance, they are visible even in very small quantities such that the control of water pollution has become of high importance nowadays. Government legislations are therefore forcing dye using industries to treat their effluent to high standards. Colour removal by conventional treatment methods such as ozonation, bleaching, hydrogen peroxide/UV, electrochemical techniques are not adequate due to the fact that most textile dyes have complex aromatic molecular structures that resist degradation. The research has shown that the use of membrane filtration can be an alternative for low cost treatment methods. In this study membrane made of electrospun polyamide 6 nanofibres is used in order to investigate the effects of increasing temperature on dye removal (sorption) using sorption filtration method. C.I Acid blue 41, C.I Acid yellow 42 and C.I Acid blue 78 were used to determine the accumulated mass of each on the electrospun polyamide 6 nanofibre membrane, using the temperatures of between 20 ?C and 60 ?C. The accumulated mass could decrease with the increase in temperature till the glass transition temperature of the membrane such that above this temperature the accumulation of dye was increased. All the results were based on spectrophotometric analysis and also the SEM was used for image analysis in order to analyze the effects of increasing temperature on the surface of the membrane. All the dyes tested could follow the Langmuir isotherm such that the curves for the experiments and the ones for Langmuir isotherm were comparable with very small differences. The results also show that C.I Acid Blue 41 had the highest values of sorption capacity compared to Acid Blue 78 and Acid Yellow 42, this was because of the highest saturation value (S) compared to the other two. Determination of sorption capacity at equilibrium was tested after a period of 10 days with increasing mass of fibre from 1 piece up to 10 pieces of 30mm x 30mm nanofibrous membrane with constant concentration and volume of solutions used.
  • Item
    Electrical Conductivity of PLA Films Reinforced With Carbon Nano Particles from Waste Acrylic Fibers
    (2018-01-01) Naeem, Salman; Gilani, Syed Qummer Zia; Baheti, Vijay; Wiener, Jakub; Militký, Jiří; Javed, Saima; Ali, Azam; Javed, Zafar; ul Hassan, Syed Zameer
    The acrylic fibrous waste was effectively transformed into activated carbon through physical activation in single stage carbonization under charcoal using at different carbonization temperatures 800, 1000 and 1200 degrees C. The characterization of carbonized fibers was performed with the help of XRD and EDX in order to find out the degree of crystallinity and proportion of different elements in carbonized fibres prepared at different temperatures. Later on, the carbonized fibers were pulverized in dry conditions by high energy planetary ball milling to get activated carbon micro/nano particles. In addition to refinement of size, the electrical conductivity of pulverized carbon particles was found to increase with increase in milling time. Subsequently, the particles were incorporated into poly lactic acid (PLA) in different loadings from 1 to 10% to develop conductive green composite films The composite films were then characterized for electrical, thermo-mechanical and thermal properties.
  • Thumbnail Image
    Item
    Finishing of basalt fibres
    (Technická Univerzita v Liberci, 2011-01-01) Dlamini, Nkululeko Muzi Patrick; Wiener, Jakub
    Basalt fibre (BF) is a material made from extremely fine fibres of basalt, which is composed of the minerals plagioclase, pyroxene, and olivine. It is almost similar to its mineral fibre counterparts, like carbon fibre and glass fibre, having better physical mechanical properties than glass fibre, but being significantly cheaper than carbon fibre. In this study a series of investigations are conducted, to explore and develop other techniques which could be useful for basalt fibre finishing. The first investigation is piloted by qualitatively analysing the atomic element(s) composition of basalt fibre, with a use of Laser-Induced Breakdown Spectroscopy (LIBS). The inter-facial interaction relationship between basalt fibre, acids and alkalis is also explored as a means to determine the degree of BF resistance against corrosion. An attempt to modify BF surface properties is conducted by means of IR laser (CO2 laser) irradiation. A degree of BF surface damage due to different CO2 laser beam intensity levels is classified accordingly. An attempt to deposit carbon on BF surface, by IR laser method is explored. Lastly, a carbon matrix (C-matrix) is prepared from different concentrates of sucrose solution. This C-matrix is then used as a binding resin for BF reinforced composite material. Porous carbon composites rods (carbon electrode) are produced and tested for electrical conductivity, mechanical properties and thermo stability. To assess and evaluate properties of the specimens prepared, the following instruments are used: Scanning Electron microscopy (SEM), Tera 2300 mechanical tester, X-ray florescence (XRF), and Dynamic mechanical analyser (DMA).
  • Thumbnail Image
    Item
    Flame resistance behavior of cotton fabrics coated with bilayer assemblies of ammonium polyphosphate and casein
    (2019-03-01) Faheem, Sajid; Baheti, Vijay; Tunak, Maros; Wiener, Jakub; Militky, Jiri
    This research report discusses the intumescent flame resistance and physiological comfort of cotton fabrics after being coated with bilayer assemblies of different concentrations of ammonium polyphosphate (APP) and casein solutions. The flame resistance was investigated using horizontal flame propagation, cone calorimetry and thermo-gravimetric analysis, whereas physiological comfort was estimated in terms of air permeability, water vapor permeability and stiffness testing. From cone calorimetry results, the coated fabrics showed very slow combustion kinetics as the concentration of casein or APP was increased. Although, higher concentration of casein was found to produce higher char residue, but the physiological comfort properties were deteriorated beyond 5wt% casein. The images of burnt samples confirmed the formation of a distinct intumescence layer of char residue and it was also validated from the measurements of thermal conductivity of char residues. In this way, the presented work showed that the casein could perform number of functions such as catalyzed dehydration, accelerated charring and intumescent char formation in APP based intumescent systems.
  • Thumbnail Image
    Item
    Flame Retardancy, Physiological Comfort and Durability of Casein Treated Cotton Fabrics
    (2019-07-23) Faheem, Sajid; Baheti, Vijay; Nahid, Nazia; Tunak, Maros; Wiener, Jakub; Militký, Jiří
    The present work was aimed to develop the flame retardant textiles for prevention of second-degree burn injuries from low intensity heat flux accidents. The different concentration of casein suspension was applied on cotton fabrics and their thermo-oxidative properties, flame retardant behavior as well as physiological comfort were examined. From thermo gravimetric analysis, the percentage increase in char residue indicated improvement in thermo-oxidative properties. The maximum improvement in flame retardant behavior was found in case of 30 w/v % casein suspension due to higher production of thermally stable char. Their SEM micrographs also showed the formation of stronger and coherent char with presence of local intumescence. Furthermore, for estimating small differences in burn length and burn area, the flame propagation was studied in detail using the image analysis. The lower concentration of casein below 20 w/v % was found to provide adequate flame retardancy with acceptable physiological comfort and mechanical properties. Finally, the short term durability of casein treatment was verified under the effect of washing and ageing conditions.
  • Thumbnail Image
    Item
    Fotochemická metoda vytváření nanočástic stříbra v textilních vláknech
    (Technická Univerzita v Liberci, 2007-01-01) Hübnerová, Kristina; Wiener, Jakub
    Tato diplomová práce se zabývá vytvářením nanočástic stříbra v textilních vláknech pomocí fotochemické metody. Je rozdělena na teoretickou a experimentální část. V teoretické části jsou popsány současné poznatky o nanočásticích stříbra a o fotochemické metodě jejich vytváření. V rámci experimentátlní části práce byly pomocí fotografického postupu vytvářeny nanočástice stříbra přímo v bavlněných vláknech a v celofánové fólii. Postup s použitím bavlněných vláken byl optimalizován a tímto způsobem připravené standardní vzorky byly testovány na barevnost, stálost v otěru a v praní, baktericidnost a elektrickou vodivost. Dále byla u standardních vzorků provedena analýza množství stříbra ve vláknech a vzorky byly snímkovány rastrovacím elektronovým mikroskopem (REM).