Influence of special finishes on denim properties

This study deals with imparting special effects on denim fabric using novel finishes. Special finishes are applied on desized indigo dyed cotton fabric. Their impacts are evaluated concerning breaking force, spectral characteristics and surface appearance. The results show significant differences among modern special treatments, thus providing important data on the processing of denim. All finishes show decrease in breaking force and cause changes in spectral characteristics of the treated samples. The results indicate that some of them are acceptable only as an effective segment on a garment

Impact of washing and sterilization on properties of fabrics used for medical applications

This paper reports a study on the characterization of cellulosic, polyester/cotton (PES/cotton) and Tencel fabrics as well as PES/PU/PES laminate used for medical applications, before and after frequent washing and sterilization. The impact of washing and sterilization is analysed by tensile properties, spectral changes and surface characterization. The results indicate that, during washing and sterilization, cellulosic fabrics show prominent changes of all studied properties when compared to PES/PU/PES laminate

Metode za preliminarna određivanja anionskih, kationskih i neionskih surfaktanata

Detergents present a major environmental problem due to large quantities of surfactants released from laundries. For this reason, it is important to apply an appropriate analytical method for their determination. In this work, we propose two simple, fast and inexpensive analytical methods for anionic, cationic and non-ionic surfactant determination: thin layer chromatography (TLC) separation for qualitative screening and quantitative potentiometric determination with ion-selective electrodes. These methods have been chosen because of their many advantages: rapidity, ease of operation, low cost of analysis and a wide variety of TLC application possibilities. The advantage of potentiometric titration is its very high degree of automation and very low detection limits obtained with different ion-selective electrodes applied for different surfactants.Danas se različite površinski aktivne tvari (anionske, neionske, kationske i amfoterne) upotrebljavaju u ogromnim količinama u različitim industrijama i domaćinstvima, što čini velik problem za okoliš. Njihova je industrijska primjena proširena na proizvodnju kozmetike, metala, papira i kože, pa se oni zbog toga mogu nalaziti u otpadnim vodama tih industrija u velikim količinama. U Europi se upotrebljava 4 250 000 tona detergenata i 1 190 000 tona omekšivača godišnje. Mnoge od uobičajenih površinski aktivnih tvari imaju izrazito toksično i štetno djelovanje na okoliš i na ljudsko zdravlje, pa su zakonski propisi koji kontroliraju njihovo postojanje u otpadnim vodama dosta strogi: granice za otpuštanje površinski aktivnih tvari u tokove otpadnih voda u Hrvatskoj kreću se u rasponu od δ= 0,05 do 0,10 mg L-1. Na toksičnost i biorazgradivost tih tvari u okolišu utječu mnogi fizikalni, kemijski i biološki čimbenici u međudjelovanju. Kompleksan sastav detergenata u kojima se površinski aktivne tvari miješaju s ostalim komponentama također dovodi do sinergističkog učinka. Nadalje, detergenti odnosno površinski aktivne tvari u njihovom sastavu mogu utjecati na biorazgradivost i toksičnost ostalih komponenata u okolišu. Zbog toga je vrlo važno razviti i primijeniti odgovarajuću a pri tome ne skupu analitičku metodu za određivanje površinski aktivnih tvari u detergentima. Ovim radom predlažu se dvije jednostavne i brze analitičke metode za određivanje anionskih, kationskih i neionskih površinski aktivnih tvari: tankoslojnu kromatografiju za kvalitativno određivanje te njihovo kvantitativno određivanje potenciometrijskom titracijom s ionsko selektivnim elektrodama. Pokazano je da je najbolja separacija i identifikacija istraživanih komponenata postignuta pomoću razvijača izoamil alkohola na podlozi silikagela 60 F254 s, detekcija je provedena pod UV lučnicom pri l = 254 nm. Nakon kromatografske identifikacije komponenata, obavljena je potenciometrijska titracija surfaktanata uz primjenu različitih ion selektivnih elektroda i titranata (kationski je titriran sa c = 0,004 mol L-1 natrij dodecil sulfatiom pri pH 10, anionski sa c = 0,004 mol L-1 Hiaminom 1622 kod pH 3, a neionski sa c = 0,01 mol L-1tetrafenilboratom kod pH 10). Te dvije metode pokazale su se kao vrlo dobra kombinacija za određivanje anionskih, kationskih i neionskih površinski aktivnih tvari. Prednost potenciometrijske titracije je visok stupanj automatizacije i vrlo niske granice detekcije koje postižu različite ion selektivne elektrode. Tankoslojna kromatografija također pruža mnoge prednosti nad ostalim analitičkim metodama: niski troškovi, brzina te jednostavnost analize omogućuju uvođenje ove metode u mnoge laboratorije koji se bave analizom detergenata

Karakterizacija polimernih nanofiltracijskih membrana

As membrane processes are increasingly used in industrial applications, there is a growing interest in methods of membrane characterization. Traditional membrane characteristics, such as cut-off value and pore size distribution, are being supplemented by membrane surface characteristics, such as charge density or zeta potential and hydrophobicity. This study, therefore, characterizes the three different polymeric membranes used (NFT-50, DL and DK). The molecular mass cut-off (MMCO) value was determined using a set of reference solutes within the molecular range 150-600 Da, whereas streaming potential measurements enabled quantification of the surface charge characteristics. Hydrophobicity was studied using contact angle measurements. The results indicated that even though all three membranes had very similar layer compositions which consisted of poly(piperazneamide), as top layers they showed different values of measured quantitive. The NFT-50 membrane had the lowest MMCO value and the most hydrophilic membrane surface, followed by DK and DL. Membrane fouling as measured by flux reduction was determined by streaming potential measurements and accompanied by a positive change in zeta potential.Znanstvena istraživanja metoda za karakterizaciju membrana za pročišćavanje otpadnih voda u stalnom su porastu. Tradicionalne metode karakterizacije veličinom i raspodijelom pora dopunjuju se metodama karakterizacije određivanjem zeta-potencijala i hidrofilno/hidrofobnih svojstva. Stoga su u ovom radu karakterizirane tri različite polimerne nanofiltracijske membrane NFT-50, DL i DK karakterizirane veličinom MMCO odabirom tri referentne otopine molekulske mase 150-600 Da. Elektrokinetičke karakteristike tih membrana vrednovane su pomoću potencijala strujanja a hidrofobnost pomoću kontaktnog kuta. Rezultati istraživanja ukazuju na to da su, unatoč gotovo jednakom gornjem sloju kompozitnih membrana, mjerne veličine različite. Najnižu MMCO vrijednost i najvišu hidrofilnost ima NFT-50 membrana kojoj slijede DK i DL. Smanjivanje protoka permeata ukazuje na začepljivanje membrana, koje je izmjereno pomoću potencijala strujanja te rezultiralo smanjivanjem zeta-potencijala

Influence of special finishes on denim properties

170-174This study deals with imparting special effects on denim fabric using novel finishes. Special finishes are applied on desized indigo dyed cotton fabric. Their impacts are evaluated concerning breaking force, spectral characteristics and surface appearance. The results show significant differences among modern special treatments, thus providing important data on the processing of denim. All finishes show decrease in breaking force and cause changes in spectral characteristics of the treated samples. The results indicate that some of them are acceptable only as an effective segment on a garment

Bioinnowacyjna metoda odtłuszczania tkanin bawełnianych za pomocą kwasowej i neutralnej pektynazy

Using biotechnology during textile processing has been known for years due to its environmental benefits and special performance of enzymes in comparison with the conventional processing of textiles. This paper deals with the bioscouring of cotton fabric with acid and neutral pectinases in comparison with alkali scouring. Variations in technological procedures, as expressed through pad-roll and exhaustion, were also identified for the bioscouring of cotton fabrics. The varied impacts of alkali, acid, and neutral pectinases on the properties of cotton fabrics throughout the processing technology were evaluated for electrokinetic phenomena, hydrophilicity, mechanical and chemical degradation, inorganic residues, and whiteness.Biotechnologie dla obróbki tekstyliów stosowane są z powodzeniem od lat ze względu na brak negatywnego oddziaływania na środowisko oraz korzystne oddziaływanie enzymów na właściwości obrabianych tekstyliów w stosunku do technologii konwencjonalnych. Praca dotyczy odtłuszczania bawełnianej tkaniny za pomocą kwasowej i neutralnej pektynazy w porównaniu z odtłuszczaniem zasadowym. Badano również szereg modyfikacji tej technologii. Wpływ zasadowej, kwasowej i neutralnej obróbki tych tkanin badano poprzez zjawiska elektrokinetyczne, hydrofilowość, mechaniczną i chemiczną degradację oraz biel obrobionych tkanin

Impact of washing and sterilization on properties of fabrics used for medical applications

426-431This paper reports a study on the characterization of cellulosic, polyester/cotton (PES/cotton) and Tencel® fabrics as well as PES/PU/PES laminate used for medical applications, before and after frequent washing and sterilization. The impact of washing and sterilization is analysed by tensile properties, spectral changes and surface characterization. The results indicate that, during washing and sterilization, cellulosic fabrics show prominent changes of all studied properties when compared to PES/PU/PES laminate

Wpływ suchego prania na efekt ekranowania fal elektromagnetycznych tkanin podszewkowych

The research deals with the protective properties of sewn interlining fabric (IF) intended for pockets of jackets, trousers and other garments in order to protect the user from the harmful effects of microwave radiation from mobile devices. The IF was produced from polyamide filaments coated with copper. Measurements of the electromagnetic shielding effectiveness of the face and reverse side of the IF were made at frequencies of 0.9, 1.8, 2.1 and 2.4 GHz, which were repeated after the dry cleaning process and also following ironing in 10 cycles. Surface modification of the IF tested was examined by scanning electron microscopy - SEM. The results showed a complete loss of material protective properties after ten dry-cleaning and ironing cycles. Damage to the surface copper layer that allowed the passage of electromagnetic micro waves in the fabric cycles was also confirmed by SEM micrographs.Badania dotyczą właściwości wszywanych tkanin podszewkowych przewidzianych dla kieszeni spodni, marynarek i innych ubiorów zabezpieczających użytkownika przed szkodliwym działaniem promieniowania mikrofalowego telefonów komórkowych. Tkaniny podszewkowe wyprodukowano z włókien poliamidowych pokrytych miedzią. Zbadano pochłanianie fal elektromagnetycznych przez przygotowane próbki, przy czym różnicowano obydwie strony w stosunku do źródła promieniowania. Przy badaniach stosowano częstotliwości 0.9, 1.8, 2.1 i 2.4 GHz. Badania prowadzono przed i po 10 suchych praniach połączonych z prasowaniem. Wyniki badań wskazują na całkowitą utratę właściwości ekranujących przez materiał po 10 suchych praniach z prasowaniem. Badania tłumienia potwierdzono mikrofotografiami SEM

Analityczna ocena rozkładu termicznego dzianin bawełniano-modakrylowych

Fabric flammability is affected by various factors such as the fibre composition, fabric construction, FR (flame retardant) finish, oxygen concentration and environmental conditions (moisture content, heat.). Inherently FR fabrics are synthetics which have been changed at the molecular level to make the fabrics thermally stable and able to pass FR tests.The thermal properties of knitted fabrics produced from cotton, modacryl and their blends were investigated in this paper. The design of FR knitted fabrics and an optimal blend ratio were evaluated by different thermoanalytical methods: the flame behaviour and thermal stability with the limited oxygen index (LOI), thermal gravimetric analysis (TGA),coupled thermal gravimetry - Fourier transform infrared technique (TG-FTIR) and microscale combustion calorimetry (MCC). Surface characterisation of the knitted fabrics designed was evaluated by the streaming potential method. Knitted fabric in the blend ratio C50:M50 proved to possess the most favourable FR characteristics, additionally confirmed by optimal hydrophilic properties evaluated through zeta potential measurement.Na palność wyrobu mają wpływ różne czynniki, takie jak skład włókien, budowa wyrobu, wykończenie nadające mniejszą palność, stężenie tlenu i warunki środowiskowe (zawartość wilgoci, ciepło). Wyroby o zmniejszonej palności są syntetykami, które zostały zmodyfikowane na poziomie molekularnym, tak aby uczynić z nich wyroby stabilne termicznie, które mogą pomyślnie przejść testy palności. W pracy badano właściwości cieplne dzianin wytwarzanych z bawełny, modakrylu i ich mieszanek. Optymalny stosunek mieszanki oceniono różnymi metodami termoanalitycznymi tj.: zachowanie płomienia i stabilność termiczna z ograniczonym wskaźnikiem tlenu (LOI), termiczna analiza grawimetryczna (TGA), sprzężona grawimetria cieplna - technika podczerwieni z transformatą Fouriera (TG -FTIR) i mikroskopowa kalorymetrii spalania (MCC). Charakterystykę powierzchni dzianin oceniono metodą potencjału strumieniowego. Dzianiny o stosunku mieszania C50:M50 okazały się posiadać najbardziej korzystne cechy zmniejszonej palności, dodatkowo potwierdzone optymalnymi właściwościami hydrofilowymi ocenianymi za pomocą pomiaru potencjału zeta