The innovation describes the method for the synthesis of novel aliphatic polyesteramide dendrimers.
F.13 Development of new production methods and tools or processes
COBISS.SI-ID: 4956954Mentorship to a Ph.D. student: M. Žigon was a mentor to David Pahovnik at the Faculty of Chemistry and Chemical Technology, University of Ljubljana. David Pahovnik defended his Ph.D. thesis on /20/04/2012. Nanostructured polyanilines (PANIs) of various morphologies were synthesized by the oxidative polymerization of aniline with ammonium peroxodisulfate in acidic aqueous medium containing ionic liquids with imidazolium, pyridinium, pyrrolidinium and quaternary ammonium cations. In the case of imidazolium type ionic liquids, the length of one of the side chains was varied using methyl, ethyl, butyl, octyl, decyl and hexadecyl groups. The influence of the reaction conditions such as the aniline to ionic liquid mole ratio, the initial aniline concentration and the type of the ionic liquid on the morphology and properties of formed PANIs was investigated. The presence of ionic liquids in the reaction mixture controls the PANI morphology toward nanowires and various complex threedimensional structures, as it was observed by the scanning electron microscopy (SEM). These nanostructures strongly contrast with the agglomerated granular particles morphology pattern typical of PANIs prepared by the standard procedure. The type of ionic liquid and the aniline to ionic liquid mole ratio have the highest impact on the PANI morphology. The UV-Vis, IR and Raman spectra as well as size exclusion chromatography analyses of PANIs have shown that the chemical structure and molecular weight characteristics are almost not affected by ionic liquids, which indicates that their presence does not affect formation of PANI molecules but only their consecutive assembly during aniline polymerization with peroxodisulfate anions. The analysis done by the dynamic light scattering method indicated that ionic liquids form micelles in 1M HCl. The micelles most likely act as soft templates that assemble aniline molecules and/or growing PANI chains into particular nanostructures and/or their precursors. As the micelle architecture is, in general, a function of the type of IL and the IL/aniline concentration ratio, differently structured PANI nanoparticles can be formed: columnar micelles can give rise to nanowires and lamellar micelles to PANI lamellas.
D.09 Tutoring for postgraduate students
COBISS.SI-ID: 261579520Mentorship to a Ph.D. student: E. Žagar was a mentor to Tina Šmigovec Ljubič at the Faculty of Chemistry and Chemical Technology, University of Ljubljana. Tina Šmigovec Ljubič defended her Ph.D. thesis on /15/10/2012. Research focused on the characterization of three linear poly(styrene-b-t-butyl methacrylate) copolymers, PS-b-PtBMA, composed of polystyrene (PS) block of comparable lengths and shorter poly (t-butyl methacrylate) (PtBMA) blocks of different lengths. We tried to separate their mixture in weight ratio 1/1/1 into individual components by various chromato-graphic techniques. Second part of research was a comprehensive characterization of poly(styrene-b-isoprene) ((PS (PI)x) star copolymers which were synthesized by anionic polymerization of polystyrene (PS) and polyisoprene (PI) block and selectively chlorosilane chemistry. PS(PI)x copolymers (x = 2, 3, 5 and 7) differed in the length of the PI block, which shortened by increasing the number of PI arms. We used various separation (SEC, RP-LAC, 2D LC) and characterization techniques (UV-MALS-RI multidetection SEC system, NMR and MALDI-TOF MS). Most effective separation and characterization of individual components was achieved by RP-LAC, which separates molecules according to their chemical composition, and the subsequent analysis of collected fractions, which eluted from the RP-C18 column, with SEC/UV-MALS-RI technique. All PS(PI)x copolymers include homo-PS and homo-PI and high MW (PS)y(PI)z (y) 1) species in smaller quantities. Their content was higher in the PS(PI)5 and PS(PI)7 than in PS(PI)2 and PS(PI)3 copolymers. Principal component of PS(PI)2 copolymer was component with the predicted structure. PS(PI)x (x = 3, 5 and 7) copolymers contain stars with fewer PI arms than predicted by the theoretical number. These results are in line with the average chemical composition of the copolymers, determined in the proton NMR spectra of the samples and the identification of individual components by MALDI-TOF MS.
D.09 Tutoring for postgraduate students
COBISS.SI-ID: 263881216Nanostructured polyanilines (PANI) of various morphologies were synthesized by polymerization of aniline with ammonium peroxodisulfate in acidic aqueous medium. The influence of the type of IL and the aniline/IL mole ratio on the morphology and properties of formed PANIs was investigated. Ionic liquids used (IL) with imidazolium, pyridinium and quaternary ammonium cations were used. In the series of imidazolium ILs the lenght of the alkyl side chain was varied. The presence of ionic liquids in the reaction mixture controls the PANI morphology toward nanowires and various complex two- and three-dimensional structures, in contrast to the agglomerated granular particles, which is typical morphology of PANIs prepared in the absence of IL, as it was observed by the scanning electron microscopy (SEM). The UV-Vis, IR and Raman spectra of PANIs showed that the used ILs do not affect the chemical structure of PANI, which indicates that they do not affect the formation of PANI molecules but only their assembling during polymerization. The DLS measurements indicate that ILs as well as their mixtures with an oxidant and aniline form in 1 M HCl ordered micellar structures. The micellar structures most likely act as soft templates that assemble growing PANI chains and/or aniline molecules into particular nanostructures and/or their precursors. The fact that the structure of PANI nanoparticles is, in general, a function of the type of IL and IL/aniline concentration ratio, indicates that the architecture of micelles depends on the same variables.
B.04 Guest lecture
COBISS.SI-ID: 5067546