20.500.12556/DKUM-79346 Reološka in fizikalna karakterizacija premaznega kompozita in njegovih komponent magistrsko delo Rheological and physical characterisation of coatings and their components Magistrsko delo predstavlja obširno fizikalno in reološko karakterizacijo tekočih in utrjenih polimernih vzorcev. Delo je osnovano na izvedbi dinamičnih mehanskih analiz, s katerimi smo ovrednotili lastnosti utrjenega polimernega materiala. Vzorci so bili pripravljeni s tremi vezivi in dvema monofunkcionalnima monomeroma ter enim difunkcionalnim monomerom, s katerimi smo v različnih medsebojnih razmerjih sintetizirali polimerne materiale z različnimi mehanskimi lastnostmi. Z reološkimi meritvami smo določili reološke lastnosti tekočih vzorcev. Z dinamično mehansko analizo (DMA) utrjenih vzorcev smo spremljali medsebojne razlike v mehanskih lastnostih pri delovnih temperaturah (T) 25,00 °C in 60,00 °C. Karakterizacijo utrjenih vzorcev smo začeli z amplitudnim testom, na podlagi katerega smo določili linearno viskoelastično (LVE) območje sintetiziranih vzorcev. Iz dobljenih diagramov smo lahko ločili vzorce na podlagi togosti ali mehkobe, prav tako je bil iz rezultatov razviden temperaturni vpliv na mehanske lastnosti sintetiziranih vzorcev. Pri tristopenjskem testu oscilacija-oscilacija-oscilacija (analiza 3TT) je bilo razvidno, da se vzorci, merjeni pri T 25,00 °C, pod vplivom strižne deformacije hitro povrnejo v začetno stanje. S tritočkovnim upogibnim testom smo pridobili diagram odvisnosti med raztezkom in obremenitvijo, iz katerega je bila razvidna trdnost vzorcev, kot tudi maksimalne vrednosti upogibnih raztezkov, torej vpliv viskozne komponente na obnašanje vzorcev. Z nateznim testom smo pridobili podobne informacije kot pri tritočkovnem upogibnem testu, a so bili rezultati manj zanesljivi zaradi nezanemarljivega vpliva senzorskega sistema, predvsem na mehkejše vzorce. Za določevanje temperature steklastega prehoda (Tg) smo najprej uporabili diferenčno dinamično kalorimetrijo (DSC-instrument), s katero smo pri večini vzorcev imeli težave pri pridobivanju sprejemljivih rezultatov. Z metodo DMA so bili rezultati sprejemljivi in ponovljivi. Najvišjo vrednost Tg, in sicer 120,05 °C, smo z metodo DMA določili pri vzorcu TEGDMA + 6040. Na koncu smo opravili še multifrekvenčni test z analizo superpozicije temperature in časa (TTS). Ta se je izkazala za zelo uporabno pri trdnejših in odpornejših vzorcih, pri katerih smo pridobili informacije glede daljše življenjske dobe pri izbranih pogojih. This master's thesis describes an extensive physical and rheological characterization of wet and cured polymer samples. The work was based on establishing dynamic mechanical analysis, by which we valued the properties of cured polymer material. The samples were prepared with three different resins, two different monofunctional monomers and one difunctional monomer. To prepare the samples with different mechanical properties, different mixtures of the components with various ratios were used. The physical properties of the wet samples were determined through rheological analyses. By using dynamic mechanical analysis (DMA) the individual differences in mechanical properties of cured samples at 25,00 °C and 60,00 °C were measured. The cured samples were characterized with an amplitude sweep first to determine the linear viscoelastic (LVE) region of synthesized samples. The samples were separated based on their toughness and softness. From the obtained informations by amplitude sweeps, the influence of the temperature (T) on the mechanical properties of the samples was evident. The three interval test (3TT) oscillation – oscillation – oscillation showed that the samples measured at 25,00 °C under the influence of high shear rate, quickly recover into their original state. By performing a three point bending test stress – strain diagram is acquired which is used to determine the level of toughness of the prepared samples, as well as the maximum stain values. Consequently, the influence of the viscous components on the sample's behaviour was determined. By performing tensile testing similar outcomes as with the three-point bending test were acquired. However, the results were less reliable based on the significant influence of sensors especially on the softer samples. Differential scanning calorimetry (DSC) and DMA were used to determine the glass temperature (Tg). DSC was shown to be difficoult in obtaining the Tg values, however, DMA gave repeatable Tg values of the samples. The highest Tg value of 120,05 °C was obtained with DMA for the sample TEGDMA + 6040. Lastly, multifrequency testing with time – temperature superposition (TTS) analysis was performed. This method was used to determine the lifespan of the tougher samples at specified conditions. reologija DMA DMTA fotopolimerizacija rheology DMA DMTA photopolymerisation true true false [T. Drobnič] Slovenski jezik Angleški jezik Magistrsko delo/naloga 2021-06-15 16:26:02 2021-07-09 13:36:24 2022-08-09 20:27:07 0000-00-00 00:00:00 2021 0 Maribor 0 Maribor XVI, 123 str. 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 532.135:678.017(043.2) 72416515 MAG_Drobnic_Tea_2021.pdf MAG_Drobnic_Tea_2021.pdf 1 8228FA543B1C7E57818789749C559D9D 321c76c99375564fb9fecdba0a715a86e764ab8bcb6166f1978de029a619ab06 e2f941a5-deee-11eb-b8c8-00155d581298 20.500.12556/dkum/2b1158d9-73c1-4375-88e6-9245d4bd3b0c https://dk.um.si/Dokument.php?lang=slv&id=151155 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0