Obtaining of bioactive nanostructured materials based on cellulose and chitosan

Cilj istraživanja ove doktorske disertacije je dobijanje bioaktivnih nanostrukturnih materijala na bazi regenerisane celuloze (RC), TEMPO oksidisanih celuloznih nanofibrila (TOCN) i hitozana (CS). Istraživanja sorpcionih svojstava ultra-tankih filmova na bazi RC i TOCN, primenom kvarc-kristal mikrovage sa praćenjem disipacije (QCM-D), omogućila su razumevanje njihovih interakcija sa vodom, CS i proteinima, kao i određivanje parametara procesa za dobijanje bioaktivnih nanostrukturnih materijala (filmova i tkanina) na bazi RC, TOCN i CS. Dobijeni nanostrukturni ultra-tanki filmovi, s obzirom na njihovu multifunkcionalnost (visok kapacitet sorpcije vode, protein-odbijajuća i antibakterijska svojstava), predstavljaju materijale koji mogu naći primenu kao obloge u terapiji rana. Tekstilni materijali sa antibakterijskim i antioksidativnim svojstvima dobijeni su funkcionalizacijom viskozne tkanine CS, nanočesticama hitozana (NCS) i nanočesticama hitozana sa inkorporiranim jonima cinka (NCS+Zn). U cilju poboljšanja antibakterijskih, antioksidativnih svojstava, kao i njihove postojanosti na pranje, viskozne tkanine su pre funkcionalizacije pred-tretirane naslojavanjem sa TOCN i TEMPO oksidacijom radi uvođenja karboksilnih i aldehidnih grupa pogodnih za ireverzibilno vezivanje CS, NCS i NCS+Zn. Uticaj pred-tretmana na vezivanje CS, NCS i NCS+Zn, hemijska, elektrokinetička, morfološka, sorpciona, mehanička i bioaktivna svojstva pred-tretiranih i hitozanom funkcionalizovanih tkanina ispitan je primenom FTIR, ICP-OES, SEM i elementalne analize, merenjima zeta potencijala, kapilarnosti, sadržaja vlage, prekidne jačine, antibakterijskih i antioksidativnih svojstava. Postojanost na pranje viskoznih tkanina funkcionalizovanih hitozanom praćena je kroz promene u sadržaju hitozana i cinka, elektrokinetičkim, antibakterijskim i antioksidativnim svojstvima nakon višestrukih ciklusa pranja. Sa oba pred-tretmana postignuto je poboljšanje adsorpcije CS, NCS i NCS+Zn, kao i antibakterijskih svojstva funkcionalizovanih materijala koja su postojana na pranje. Sve dobijene tkanine pokazale su dobra antioksidativna svojstva, bez značajnog pogoršanja nakon višestrukih ciklusa pranja. S obzirom na postignuta antibakterijska i antioksidativna svojstva, viskozne tkanine funkcionalizovane CS, NCS i NCS+Zn mogu naći primenu kao medicinski tekstilni materijali u prevenciji i terapiji rana.The aim of this doctoral dissertation is obtaining of bioactive nanostructured materials based on regenerated cellulose (RC), TEMPO oxidized cellulose nanofibrils (TOCN) and chitosan (CS). The research on the sorption properties of ultra-thin films based on RC coated with TOCN, by using a quartz crystal microbalance with dissipation (QCM-D), helped us to understand their interactions with water, CS, and proteins, and to determinate the parameters of the processes for obtaining of bioactive nanostructured materials (films and fabrics) based on RC, TOCN and CS. Obtained nanostructured ultra-thin films, thanks to their multifunctionality (high water absorbance capacity, protein-repellence and antimicrobial properties), represent materials which could be applicable as dressings in wound therapy. Textile materials with antibacterial and antioxidative properties were obtained by functionalization of viscose fabrics with CS, chitosan nanoparticles (NCS) and chitosan nanoparticles with embedded zinc ions (NCS+Zn). To improve antibacterial, antioxidative properties, as well as their washing durability, viscose fabrics were pre-treated, before functionalization, by coating with TOCN and TEMPO oxidation in order to introduce carboxyl and aldehyde groups suitable for irreversible attachment of CS, NCS and NCS+Zn. The influence of pre-treatments on CS, NCS and NCS+Zn binding, chemical, electrokinetic, morphological, sorption, mechanical, and bioactive properties of pre-treated and chitosan functionalized viscose fabrics were evaluated by FTIR, ICP-OES, SEM and elemental analysis, measurements of zeta potential, capillarity, moisture sorption, breaking strength, antibacterial and antioxidative properties. The washing durability of chitosan functionalized viscose fabrics was monitored through changes in the chitosan and zinc content, electrokinetic, antibacterial and antioxidative properties after multiple washing. With both pre-treatments improved CS, NCS and NCS+Zn adsorption, as well as washing durable antibacterial properties of functionalized materials, were achieved. All obtained fabrics have shown good antioxidative properties, without significant deterioration after multiple washing. Based on achieved antibacterial and antioxidative properties, viscose fabrics functionalized with CS, NCS and NCS+Zn may find application as medical textile materials in wound prevention and therapy

TEMPO oksidacija u funkciji poboljsanja antibakterijskih svojstava viskozne tkanine funkcionalizovane nanočesticama na bazi hitozana

TEMPO oxidation of viscose fabric was used as a pretreatment 10 introduce carboxyl and aldehyde groups for irreversible binding of chilosan and to improve antibacterial activity and washing durability of viscose fabrics functionalized with chitosan nanoparticles withour (NCS) and with emt edded zine (NCS+ Zn). Carboxyl and aldehyde group content, electrokinetic properties, elemental analysis, inductively coupled plasma optical emission spectrometry and antibacterial testing were used to caluare the influence of TEMPO axidation on subseguent NCS and NCS+Zn binding and antibacterial properties of chitosan functionalized viscose fabrics. Anvibacterial activity of NCS and NC$+Zn functionalized viscose fabrics was preserved after multiple wasting

Obtaining of bioactive nanostructured materials based on cellulose and chitosan

Cilj istraživanja ove doktorske disertacije je dobijanje bioaktivnih nanostrukturnih materijala na bazi regenerisane celuloze (RC), TEMPO oksidisanih celuloznih nanofibrila (TOCN) i hitozana (CS). Istraživanja sorpcionih svojstava ultra-tankih filmova na bazi RC i TOCN, primenom kvarc-kristal mikrovage sa praćenjem disipacije (QCM-D), omogućila su razumevanje njihovih interakcija sa vodom, CS i proteinima, kao i određivanje parametara procesa za dobijanje bioaktivnih nanostrukturnih materijala (filmova i tkanina) na bazi RC, TOCN i CS. Dobijeni nanostrukturni ultra-tanki filmovi, s obzirom na njihovu multifunkcionalnost (visok kapacitet sorpcije vode, protein-odbijajuća i antibakterijska svojstava), predstavljaju materijale koji mogu naći primenu kao obloge u terapiji rana. Tekstilni materijali sa antibakterijskim i antioksidativnim svojstvima dobijeni su funkcionalizacijom viskozne tkanine CS, nanočesticama hitozana (NCS) i nanočesticama hitozana sa inkorporiranim jonima cinka (NCS+Zn). U cilju poboljšanja antibakterijskih, antioksidativnih svojstava, kao i njihove postojanosti na pranje, viskozne tkanine su pre funkcionalizacije pred-tretirane naslojavanjem sa TOCN i TEMPO oksidacijom radi uvođenja karboksilnih i aldehidnih grupa pogodnih za ireverzibilno vezivanje CS, NCS i NCS+Zn. Uticaj pred-tretmana na vezivanje CS, NCS i NCS+Zn, hemijska, elektrokinetička, morfološka, sorpciona, mehanička i bioaktivna svojstva pred-tretiranih i hitozanom funkcionalizovanih tkanina ispitan je primenom FTIR, ICP-OES, SEM i elementalne analize, merenjima zeta potencijala, kapilarnosti, sadržaja vlage, prekidne jačine, antibakterijskih i antioksidativnih svojstava. Postojanost na pranje viskoznih tkanina funkcionalizovanih hitozanom praćena je kroz promene u sadržaju hitozana i cinka, elektrokinetičkim, antibakterijskim i antioksidativnim svojstvima nakon višestrukih ciklusa pranja. Sa oba pred-tretmana postignuto je poboljšanje adsorpcije CS, NCS i NCS+Zn, kao i antibakterijskih svojstva funkcionalizovanih materijala koja su postojana na pranje. Sve dobijene tkanine pokazale su dobra antioksidativna svojstva, bez značajnog pogoršanja nakon višestrukih ciklusa pranja. S obzirom na postignuta antibakterijska i antioksidativna svojstva, viskozne tkanine funkcionalizovane CS, NCS i NCS+Zn mogu naći primenu kao medicinski tekstilni materijali u prevenciji i terapiji rana.The aim of this doctoral dissertation is obtaining of bioactive nanostructured materials based on regenerated cellulose (RC), TEMPO oxidized cellulose nanofibrils (TOCN) and chitosan (CS). The research on the sorption properties of ultra-thin films based on RC coated with TOCN, by using a quartz crystal microbalance with dissipation (QCM-D), helped us to understand their interactions with water, CS, and proteins, and to determinate the parameters of the processes for obtaining of bioactive nanostructured materials (films and fabrics) based on RC, TOCN and CS. Obtained nanostructured ultra-thin films, thanks to their multifunctionality (high water absorbance capacity, protein-repellence and antimicrobial properties), represent materials which could be applicable as dressings in wound therapy. Textile materials with antibacterial and antioxidative properties were obtained by functionalization of viscose fabrics with CS, chitosan nanoparticles (NCS) and chitosan nanoparticles with embedded zinc ions (NCS+Zn). To improve antibacterial, antioxidative properties, as well as their washing durability, viscose fabrics were pre-treated, before functionalization, by coating with TOCN and TEMPO oxidation in order to introduce carboxyl and aldehyde groups suitable for irreversible attachment of CS, NCS and NCS+Zn. The influence of pre-treatments on CS, NCS and NCS+Zn binding, chemical, electrokinetic, morphological, sorption, mechanical, and bioactive properties of pre-treated and chitosan functionalized viscose fabrics were evaluated by FTIR, ICP-OES, SEM and elemental analysis, measurements of zeta potential, capillarity, moisture sorption, breaking strength, antibacterial and antioxidative properties. The washing durability of chitosan functionalized viscose fabrics was monitored through changes in the chitosan and zinc content, electrokinetic, antibacterial and antioxidative properties after multiple washing. With both pre-treatments improved CS, NCS and NCS+Zn adsorption, as well as washing durable antibacterial properties of functionalized materials, were achieved. All obtained fabrics have shown good antioxidative properties, without significant deterioration after multiple washing. Based on achieved antibacterial and antioxidative properties, viscose fabrics functionalized with CS, NCS and NCS+Zn may find application as medical textile materials in wound prevention and therapy

Uticaj dugotrajnog starenja na svojstvo TEMPO oksidisanog pamuka

Cotton yarns were 2,2,6,6-tetramethy|piperidine-1-oxy radical (TEMPO) oxidized, i.e., oxidation was carried out in the presence of sodium hypochlorite, sodium bromide and TEMPO, during different time intervals (30, 60 and 120 min). Given that TEMPO oxidized cotton is prone to aging processes, the influence of long-term aging on the properties of TEMPO oxidized cotton yarns was monitored through changes in their content of carboxyl and aldehyde groups, crystallinity index and water retention value, determined immediately after TEMPO oxidations and 10 years later. The content of carboxyl and aldehyde groups was determined by the calcium acetate method, the crystallinity index by the Schwertassek method, and the water retention value by the standard centrifuge method (ASTM D 2402-78, 1978). Aged TEMPO oxidized cotton yarns showed increased content of carboxyl groups, decreased content of aldehyde groups, unchanged crystallinity index and increased water retention value.Pamučne pređe su oksidisane 2,2,6,6-tetrametilpiperidin-I-oksilradikal (TEMPO), tj. oksidisane su sa natrijum-hipohloritom, natrijum-bromidomi TEMPO, tokom različitih vremenskih intervala (30, 60 i 120 min). S obzirom na to da je TEMPO oksidisani pamuk podložan procesima starenja, uticaj dugotrajnog starenja na svojstava TEMPO oksidisanih pamučnih pređa praćen je kroz promene u njihovom sadržaju karboksilnih i aldehidnih grupa, indeksu kristalnosti i sposobnosti zadržavanja vode, određenim neposredno nakon TEMPO oksidacije i 10 godina kasnije. Sadržaj karboksilnih i aldehidnih grupa određen je kalcijum-acetatom metodom, indeks kristalnosti Schwertassek-ovom metodom, a sposobnost zadržavanja vode standardnom metodom centrifugiranja (ASTM D 2402-78, 1978). Ostarele TEMPO oksidisane pamučne pređe pokazale su povećan sadržaj karboksilnih grupa, smanjen sadržaj aldehidnih grupa, nepromenjen indeks kristalnosti i povećanu sposobnost zadržavanja vode

CELLULOSE: FROM NATURE TO HIGH PERFORMANCE MATERIALS

Celuloza kao najzastupljeniji bioobnovljivi polimer dobija na značaju kako zbog ekonomskih razloga i mnogobrojnih mogućnosti primene, tako i zbog sve veće pažnje koju prirodnim resursima i održivom razvoju poklanjaju naučna zajednica i industrija. U ovom radu dat je prikaz savremenih istraživanja u oblasti celuloze usmerenih na razumevanje procesa, unapređenje znanja i oblasti primene ovog najznačajnijeg bioobnovljivog resursa. Posebna pažnja posvećena je funkcionalizaciji celuloze i razvoju celuloznih materijala specijalnih svojstava na bazi nanofibrilisane celuloze.Cellulose, the most abundant natural and renewable polymer, gains on importance regarding to its economic value, the wide area of possible applications and due to increased attention of the industrial and the scientific community on natural resources and sustainability issues. This paper gives an overview of the current cellulose research directed towards an advanced understanding and application of this most important bioresource. Emphasis is placed on the cellulose functionalization and development of high performance tailored cellulose materials based on nanofibrillated cellulose

Obtaining of cotton yarn with improved sorption properties

U ovom radu proučavan je uticaj TEMPO- oksidacije na hemijski sastav, strukturu i svojstva pamučne pređe. Nemodifikovana i modifikovana pamučna pređa okarakterisana je sa aspekta gubitka mase, sadržaja vlage, sadržaja karbonilnih i karboksilnih grupa, indeksa kristalnosti i sposobnosti zadržavanja vode. Promene u svojstvima modifikovanih pređa u odnosu na polazni uzorak su praćene u funkciji koncentracije oksidacionog sredstva i vremena modifikovanja. TEMPO-oksidacija pamučne pređe uticala je na smanjenje mase, povećanje sadržaja vlage i indeksa kristalnosti modifikovanih uzoraka. Oksidacijom pomoću TEMPO radikala dolazi do povećanja sorpcionih svojstava pamučne pređe usled značajnijeg povećanja sadržaja karboksilnih grupa, od 0,024 mmol/g celuloze za polazni uzorak do 0,679 mmol/g celuloze za uzorak oksidisan pri najrigoroznijim uslovima. Dobijeni rezultati omogućavaju optimizaciju selektivne TEMPO-oksidacije u cilju dobijanja pamučne pređe poboljšanih sorpcionih svojstava, koja predstavlja polaznu sirovinu za dobijanje širokog spektra tekstilnih proizvoda specijalne namene.In this paper, influence of TEMPO- oxidation onto chemical composition, structure and properties of cotton yarn was studied. Unmodified and modified cotton yarn was characterized from the aspect of weight loss, moisture content, carbonyl and carboxyl group content, crystallinity index and capability to retain water. Changes in the properties of modified yarns, compared to untreated sample, were monitored as a function of oxidizing agent concentration and time of oxidation. TEMPO- oxidation of cotton yarn had influence on weight loss, increase of moisture content and crystallinity index of the modified samples. Oxidation using TEMPO radical leads to an increase in sorption properties due to the significant increase in carboxyl group content, from 0.024 mmol/g cellulose for untreated sample to 0.679 mmol/g cellulose for sample oxidized under the most rigorous conditions. Obtained results allow optimization of selective TEMPO-oxidation in order to obtain a cotton yarn with improved sorption properties, which represents a starting raw material for the preparation of a broad spectrum of high performance textile products

Comparative Analysis of Electrokinetic Properties of Periodate- and TEMPO-Oxidized Regenerated Cellulose Fabric Functionalized with Chitosan

The electrokinetic properties of materials give useful insight into the behavior of surfaces in contact with liquids and other compounds and their quantification is a powerful tool to predict their behavior during further processing and application, especially in textile materials. In this work, we perform a comparative analysis of influence of the two most common selective oxidative protocols for viscose (regenerated cellulose) fabrics on subsequent functionalization with chitosan, and cellulose fabrics’ electrokinetic properties, zeta potential in a pH range of approx. 3–10, and isoelectric point (IEP). For oxidation before deposition of chitosan, sodium periodate and 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO) were used. The content of functional groups in oxidized cellulose fabric (carboxyl and carbonyl groups) was determined by titration methods, while amino functional groups’ availability in samples with chitosan was determined using the CI acid orange 7 dye absorption method. This study reveals that the periodate oxidation (PO) of cellulose is more effective for binding chitosan onto material, which gave rise to higher availability of amino groups onto cellulose/chitosan material, which also influenced the shift in zeta potential curve towards positive values at a pH below 5. Analysis of a relationship between zeta potential increase at pH 4.4 and amino groups’ amount measured using absorption of CI acid orange 7 dye at pH 4.4 revealed dependency that can be fitted linearly or exponentially, with the latter providing the better fit (R2 = 0.75)

Influence of non-selective oxidation on the surface chemistry and sorption properties of hemp fibers

U ovom radu ispitivani su uticaji dva različita neselektivna oksidaciona sredstva, vodonik-peroksida i kalijum-permanganata, na uvedene funkcionalne grupe i sorpciona svojstva modifikovanih vlakana konoplje. Tokom primene oba oksidaciona sredstva (H2O2 i KMnO4), oksidacioni uslovi su menjani na isti način: koncentracija oksidacionih agenasa (3% i 6%), pH vrednosti (7, 9 i 11) i vremena trajanja oksidacije (10, 20 i 30 min). U zavisnosti od korišćenog oksidacionog sredstva i uslova oksidacije, dobijene su promene u količini uvedenih funkcionalnih grupa i sorpcionim svojstavima modifikovanih vlakana konoplje u poređenju sa nemodifikovanim vlaknima konoplje. Za oba oksidaciona sredstva, upotrebljena pod istim ostalim oksidacionim uslovima, povećanje sorpcionih svojstava dobijeno je jedino u slučaju oksidacije pomoću 3% H2O2, odnosno 3% KMnO4, tokom 10 minuta, pri svim pH vrednostima. U svim ostalim slučajevima, za oba oksidaciona sredstva, dobijeno je smanjenje sorpcionih svojstava, koja su okarakterisana određivanjem sposobnosti zadržavanja vode. Veće količine funkcionalnih grupa uvedene su u vlakna konoplje oksidisana kalijum-permanganatom, u poređenju sa oksidacijom vodonikperoksidom, rađenom pod istim uslovima.In this paper, the influences of two different non-selective oxidative agents, hydrogen peroxide and potassium permanganate, on the amount of introduced functional groups and sorption properties of modified hemp fibers, were investigated. Oxidative conditions were changed at the same manner for both oxidative agents (H2O2 and KMnO4): the oxidative agent concentration (3 % and 6 %), pH values (7, 9 and 11) and oxidation times (10, 20 and 30 min). Depending on the oxidative agent used and oxidative conditions, changes in the amount of introduced functional groups and sorption properties of modified hemp fibers, compared to unmodified hemp fibers, were obtained. For both oxidative agents, applied under the same oxidation conditions, the increase in sorption properties was obtained only in the case of oxidation with 3% H2O2, i.e. 3% KMnO4, for 10 minutes, at all pH values. In all other cases, for both oxidizing agents, the decreases in the sorption properties, determined as water retention values, were obtained. In the case of oxidation with potassium permanganate, the higher amounts of functional groups were introduced in oxidized hemp fibers, compared to the oxidation with the hydrogen peroxide, applied under the same oxidative conditions

TEXTILE INDUSTRY WASTE WATERTREATMENT

Jedna od najaktuelnijih tema u svetu je ekologija i zagađenje životne sredine. Ispuštanje toksičnih materija iz raznih industrijskih pogona u neposrednu okolinu dovodi do zagađenja vode, vazduha i zemljišta. U pogonima gde se proizvodni proces vrši uz mokru obradu veliki problem predstavljaju otpadne vode. Jedan od primera je proces bojenja u tekstilnoj industriji (gde postoji problem uklanjanja ostataka boja kao organskog zagađivača iz vode). Postoje različiti fizičko hemijski i biološki postupci za prečišćavanje otpadnih voda. U tekstilnoj industriji se, pored otpadnih voda, generišu još dve vrste otpada a to su gasovi i čvrsti otpad. Najčešće korišćen postupak za prečišćavanje je adsorpcija.The current topic in the world is ecology, that is, preventing or at least reducing environmental pollution. The release of toxic substances from various industrial plants into the immediate environment causes pollution of water, air and soil. In plants where the production process is carried out with wet treatment, wastewater is a major problem. One example is the dyeing process in the textile industry (where there is a problem of removing dye residues as an organic pollutant from water). There are various physicochemical and biological processes for wastewater treatment. In the textile industry, in addition to wastewater, two more types of waste are generated, namely gases and solid waste. The most commonly used treatment method is adsorption