20.500.12556/DKUM-99805 Polimerizacija akrilatov s svetlobno občutljivimi RAFT reagenti Polymerisation of acrylates with light-sensitive RAFT agents V diplomskem delu smo sintetizirali svetlobno občutljiv reagent za reverzibilno adicijsko-fragmentacijski prenos verige (RAFT) 2-(dodeciltiokarbonotioiltio)-2-metilpropanojsko kislino (DDMAT) in ga uporabili pri RAFT kontrolirani polimerizaciji poliakrilatov brez dodatka klasičnega fotoiniciatorja. Uspešnost sinteze DDMAT smo potrdili z infrardečo spektroskopijo s Fourierovo transformacijo (FTIR). Preverili smo kompatibilnost izbranih akrilatnih monomerov etil akrilata (EA), trimetilolpropan triakrilata (TMPTA), polietilenglikol diakrilata (PEGDA 575) in 2-etilheksil akrilata (EHA) z DDMAT za polimerizacijo ter pokazali, da je sintetiziran DDMAT tudi sam fotoodziven in lahko brez zunanjega iniciatorja neposredno sproži polimerizacijo TMPTA in PEGDA 575. Preučili smo vpliv reakcijskih parametrov (valovna dolžina in intenziteta obsevanja, molsko razmerje monomer/RAFT reagent) na potek RAFT polimerizacije. Rezultati so pokazali, da je za uspešno iniciacijo najustreznejša UV komora z volframovo žarnico valovne dolžine 365 nm, medtem ko dodatek etanola (EtOH) in odstranitev raztopljenega kisika iz reakcijske zmesi pospešita nastanek polimera. Monomera TMPTA in PEGDA 575 sta uspešno polimerizirala pri širokem naboru preučevanih molskih razmerij monomer/RAFT reagent, medtem ko pri EA in EHA polimerizacija ni bila popolna. Uspešnost polimerizacije smo pri vseh vzorcih potrdili s FTIR spektroskopijo na podlagi zmanjšanja signalov, značilnih za akrilatne dvojne vezi. Na osnovi teh ugotovitev smo pripravili 80 % porozne poliHIPE materiale na osnovi TMPTA z uporabo svetlobno občutljivega RAFT reagenta DDMAT kot edinega iniciatorja polimerizacije. Nastali materiali so imeli tipično poliHIPE morfologijo s primarnimi porami velikosti 1,26 μm−1,87 μm in specifično površino 3,16 m2/g−5,62 m2/g, medtem ko je kontrolni vzorec, pripravljen s klasično fotoiniciirano polimerizacijo, kljub primerljivi velikosti por izkazoval bistveno večjo specifično površino (15,52 m2/g). Raziskava je pokazala, da lahko svetlobno občutljiv RAFT reagent učinkovito nadomesti klasični fotoiniciator pri pripravi poliakrilatov in poliHIPE materialov. Tak pristop omogoča boljši nadzor nad procesom polimerizacije ter vodi do strukturno bolj homogenih in ponovljivih materialov. In this thesis, the light-sensitive reversible addition-fragmentation chain-transfer (RAFT) agent 2-(dodecylthiocarbonothioylthio)-2-methylpropanoic acid (DDMAT) was synthesized and employed in the RAFT-controlled polymerization of polyacrylates without the addition of a conventional photoinitiator. The successful synthesis of DDMAT was confirmed by Fourier-transform infrared (FTIR) spectroscopy. The compatibility of selected acrylate monomers, namely ethyl acrylate (EA), trimethylolpropane triacrylate (TMPTA), poly(ethylene glycol) diacrylate (PEGDA 575), and 2-ethylhexyl acrylate (EHA), with DDMAT in RAFT polymerization was investigated. The results demonstrated that the synthesized DDMAT is intrinsically photoresponsive and can directly initiate the polymerization of TMPTA and PEGDA 575 without the need for an external initiator. The influence of key reaction parameters, including irradiation wavelength and intensity, as well as the monomer-to-RAFT agent molar ratio, on the course of RAFT polymerization was systematically examined. The results showed that a UV chamber equipped with a tungsten lamp emitting at 365 nm provided the most efficient initiation conditions. Furthermore, the addition of ethanol (EtOH) and the removal of dissolved oxygen from the reaction mixture enhanced polymer formation. TMPTA and PEGDA 575 were successfully polymerized over a broad range of investigated monomer-to-RAFT agent molar ratios, whereas polymerization of EA and EHA remained incomplete under the studied conditions. Successful polymerization of all samples was verified by FTIR spectroscopy through the reduction of characteristic absorption bands associated with acrylate carbon-carbon double bonds. Based on these findings, highly porous (80%) polyHIPE materials derived from TMPTA were prepared using the photoresponsive RAFT agent DDMAT as the sole polymerization initiator. The resulting materials exhibited the characteristic polyHIPE morphology, with primary pore diameters ranging from 1.26 μm to 1.87 μm and specific surface areas between 3.16 m²/g and 5.62 m²/g. In contrast, a control sample prepared via conventional photoinitiated polymerization displayed a comparable pore size distribution but a substantially higher specific surface area of 15.52 m²/g. This study demonstrates that a photoresponsive RAFT agent can effectively replace conventional photoinitiators in the preparation of polyacrylates and polyHIPE materials. Such an approach provides improved control over the polymerization process and enables the production of structurally more homogeneous and reproducible materials. foto-RAFT polimerizacija svetlobno občutljivi RAFT reagenti poliHIPE materiali porozni polimeri akrilati photo-RAFT polymerization light-sensitive RAFT agents polyHIPE materials porous polymers acrylates true true false Slovenski jezik Angleški jezik Diplomsko delo/naloga 2026-08-26 20:04:54 2026-09-17 08:17:33 2026-09-18 03:09:56 0000-00-00 00:00:00 2026 0 Maribor 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 UN_Orehovec_Masa_2026.pdf UN_Orehovec_Masa_2026.pdf 1 ACA06A4A8C1A478E24C4D92E80CCEF6C 4a4d0cc3aae7d47300c5729041680de5d2143eccbf11d18fb5d58879b11f2af9 a8e95cc0-b1f8-11f1-b05b-00155d0001be https://dk.um.si/Dokument.php?lang=slv&id=212694 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0