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Doktorska disertacija je imala za cilj sintezu i karakterizaciju nanokompozita koji poseduju antimikrobna svojstva inovativnom metodom in situ fotoredukcije Ag+-jona na površini nanokristala TiO2 različitih oblika, prethodno deponovanih na tekstilnim materijalima. Ovakav pristup sintezi nanokompozitnih tekstilnih materijala je po prvi put realizovan u okviru ove teze..., This doctoral thesis relates to the synthesis and characterization of advanced nanocomposites which exhibit antimicrobial activity and UV protective properties. For the synthesis an innovative method based on in situ photoreduction of Ag+-ions onto the surface of differently shaped TiO2 nanocrystals, being in the form of either spherical nanoparticles or nanotubes, deposited on different textile materials was applied. Such synthesis route for the formation of textile nanocomposites has been realized for the first time in the context of this thesis...

U okviru ove doktorske disertacije izvedena je radijaciono-hemijska sinteza i karakterizacija novih nanokompozita na bazi umreţenih polimernih matrica N-izopropilakrilamida (NiPAAm) i itakonske kiseline (IK) i nanočestica srebra (Ag/P(NiPAAm/IK)). Za sintezu nanokompozita je korišćena radiolitička metoda koja omogućava umreţavanje i fino podešavanje svojstava nosača tj. polimerne matrice, ali i formiranje nanočestica srebra ţeljenih svojstava unutar polimerne matrice (in situ sinteza). Radiolitička metoda sinteze je izvedena pod dejstvom gama zračenja na kobaltnom (60Co) izvoru. Sintetisani uzorci su podvrgnuti detaljnoj fizičko-hemijskoj karakterizaciji u cilju dobijanja informacija o polimernim matricama kao nosačima i nanočesticama srebra kao nanopuniocima, ali i u cilju ispitivanja njihovog sinergističkog dejstva u nanokompozitnim sistemima.Morfologija umreţenih sistema je ispitana primenom skenirajuće elektronske mikroskopije (SEM) i mikro kompjuterizovane topografije (mikro-CT), a studija bubrenja praćenjem kinetike bubrenja u medijumima različitih pH-vrednosti i temperature, pri čemu su simulirani fiziološki uslovi. Utvrđeno je da prisustvo itakonske kiseline i inkorporacija nanočestica srebra utiču na morfologiju nanokompozita, parametre polimerne mreţe, kao i na kapacitet bubrenja.Optička svojstva nanokompozita su ispitana metodom spektroskopije u ultraljubičastoj i vidljivoj oblasti spektra (UV-Vis) i teorijskim modelovanjem primenom MiePlot 3.4 programskog paketa čiji je algoritam zasnovan na Mie-ovoj teoriji. U apsorpcionim spektrima je zapaţena karakteristična plazmonska apsorpcija sa maksimumom u opsegu od 390 nm do 412 nm, dok jemodelovanjem određeno da se vrednost prečnika nanočestica srebra kreće između 6,8 nm i 16,2 nm..., In this study, radiation-chemical synthesis and characterization of the novel nanocomposite systems based on silver nanoparticles (AgNPs) and crosslinked copolymer matrix of N-isopropylacrylamide (NiPAAm) and itaconic acid (IA) (Ag/P(NiPAAm/IA)) were performed. Radiolytic method, which is used for synthesis, enables fine tuning of properties of polymer matrix as a carrier, as well as formation of the silver nanoparticles with desired properties within polymer matrix (in situ synthesis). The radiolytic synthesis method is carried out by gamma irradiation at a cobalt (60Co) radiation facility. Synthesized samples were undergo to detailed physico-chemical characterization in order to obtain information about polymer matrix as a carrier and silver nanoparticles as a nanofillers, but also to examine their synergistic effects in the nanocomposite systems.Morphology of the crosslinked systems was performed by scanning electron microscopy (SEM) and micro computerized topography (micro-CT), while swelling study was performed by monitoring the swelling kinetics in the swelling media with different pH and temperature, i.e. in simulated physiological conditions. It has been shown that the addition of itaconic acid and incorporation of AgNPs have influences on the morphology, network parameters as well as on the swelling capacity.The optical properties of the nanocomposites were investigated by ultraviolet–visible spectroscopy (UV-Vis) and theoretical modeling using MiePlot 3.4 software package, with algorithm based on Mie's theory. Obtained absorption spectra exhibit the characteristic plasmon peak with maximabetween 390 nm and 412 nm, while the modeling has shown that the mean size of the silver nanoparticles was in the range between 6.8 nm and 16.2 nm...

Predmet istraživanja ove doktorske disertacije podrazumeva sintezunanokompozita na bazi polianilina (PANI) i nanočestica titan (IV)‐oksida (TiO2)različitih oblika novom metodom, njihovu karakterizaciju većim brojemfizičkohemijskih metoda, kao i ispitivanje mogućnosti njihove primene ufotokatalizi.PANI/TiO2 nanokompoziti sintetisani su novim, ekonomičnim postupkomhemijske oksidativne polimerizacije anilina amonijum peroksidisulfatom u vodi,bez dodatka kiseline, kalupa i površinskih modifikatora, a u prisustvu nanočesticaTiO2. Optimizacijom sinteze nanokompozita kroz variranje polaznog molskogodnosa anilina i TiO2 pronađeni su uslovi za dobijanje PANI/TiO2 nanokompozita ukojima su prisutne polianilinske nanostrukture. U disertaciji je ispitan uticajnanočestica TiO2 na tok, brzinu i prinos reakcije polimerizacije anilina kao i namorfologiju, strukturu, provodljivost i magnetna svojstva polianilina. U ciljuizučavanja potencijalne primene sintetisanih nanokompozita, ispitivana jesposobnost polianilina da senzitizira i pospeši fotokatalitičke procese na površininanočestica TiO2.Rad se tematski može podeliti u tri celine i to:1. Sinteza i karakterizacija nanokompozita na bazi polianilina i koloidnihnanočestica TiO2;2. Sinteza i karakterizacija nanokompozita na bazi polianilina i nanotubaTiO2;3. Ispitivanje fotokatalitičke aktivnosti nanokompozita na bazi polianilina ikoloidnih nanočestica TiO2.Prvi deo teze odnosi se na ispitivanje svojstava nanokompozita sintetisanihhemijskom oksidativnom polimerizacijom anilina, uz pomoć amonijumperoksidisulfata, u prisustvu koloidnih nanočestica TiO2 (d = 4, 5 nm), bez dodatka..., The subject of this PhD thesis is the synthesis of nanocomposites based onpolyaniline (PANI) and titanium (IV) oxide (TiO2) by a novel method, withoutadded acids, templates and surfactants, their characterization by variousphysicochemical methods, as well as an investigation of their potential applicationin the field of photocatalysis.PANI/TiO2 nanocomposites were synthesized by a novel, economicalmethod of oxidative polymerization of aniline with ammonium peroxydisulfate inwater, without added acid, in the presence of shaped TiO2 nanoparticles. Theoptimization of polymerization process was done by varying initial mole ratio ofaniline/TiO2. The aim was to find optimal conditions for the synthesis ofPANI/TiO2 nanocomposites containing polyaniline nanostructures. Influence ofTiO2 nanoparticles on the course, rate and yield of polymerization process ofaniline, as well as their influence on the morphology, structure, electricalconductivity and magnetic properties of polyaniline is examined. Moreover,potential application of PANI/TiO2 nanocomposites in photocatalysis and ability ofpolyaniline to sensitize TiO2 nanoparticles are investigated.Topic of this work can be divided into three main units:1. Synthesis and characterization of nanocomposites based on polyanilineand colloidal TiO2 nanoparticles;2. Synthesis and characterization of nanocomposites based on polyanilineand TiO2 nanotubes;3. The study of photocatalytic activity of nanocomposites based onpolyaniline and colloidal TiO2 nanoparticles.The first part of the thesis refers to the investigation of properties ofnanocomposites synthesized by the chemical oxidative polymerization of anilinewith ammonium peroxydisulfate, in the presence of colloidal TiO2 nanoparticles(d=4, 5 nm), without added acid. As a reference sample, pure polyaniline...