| Abstract | Aditivna tehnologija (engl. additive manufacturing, AM) predstavlja skup postupaka koji omogućuju izradu predmeta, na temelju računalnog 3D-modela, nanošenjem čestica u tankim slojevima, sloj po sloj. Tehnologije aditivne proizvodnje korištene u ovom radu su proizvodnja rastaljenim filamentom (FFF), stereolitografija (SLA) i digitalna obrada svjetlom (DLP). Prvi cilj ovog rada bio je, tehnologijama FFF, SLA i DLP na 3D-pisačima, izraditi ispitne pločice od transparentnih materijala kako bi se odredio najprikladniji materijal za
3D-ispis reaktora u kojima će se provoditi fotokemijske reakcije u trajanju od 2 sata. Za izradu modela ispitnih pločica korišten je program za računalno potpomognuti dizajn (engl. computer aided design, CAD) Fusion 360, nakon čega je uslijedio 3D-ispis istih. FFF tehnologijom izrađeni su modeli pločica od polipropilena (PP) i polietilen tereftalata obogaćenog glikolom (PETG), SLA tehnologijom oni su izrađeni od poliakrilata, dok su DLP tehnologijom izrađeni od smjese poliakrilata i epoksida. Uz to, materijali korišteni u SLA i DLP tehnologiji aditivne proizvodnje podvrgnuti su i post-obradi, odnosno procesu naknadnog očvršćivanja u trajanju od 5 i 15 minuta. Svojstva polimera korištenih za izradu pločica ispitana su testom bubrenja u otapalu acetonitrilu. Rezultati ukazuju na to da je stupanj bubrenja uzorka veći, ukoliko je vrijeme naknadnog očvršćivanja manje. Nakon provedenog ispitivanja i s obzirom na stupanj bubrenja, zaključeno je da je smola High Temp pogodna za ispis reaktora jer ima najmanji stupanj bubrenja nakon 4 sata, a iznosi 3,2 %. Osim toga, cilj rada bio je i provoditi fotokemijske reakcije u reaktoru Luzchem CCP-ICH2 u trajanju od
2 sata i pri valnoj duljini 313 nm. Za provođenje fotokemijskih reakcija korišteni su reaktori sa statičkim miješalicama i reaktori bez statičkih miješalica. Za izradu reaktora korišten je CAD program Fusion 360, nakon čega je uslijedio 3D-ispis istih. Reaktori su zatim podvrgnuti post-obradi u trajanju od 5 minuta. Fotokemijske reakcije provodile su se kako bismo vidjeli postoji li razlika u dobivenim produktima tijekom korištenja reaktora sa statičkim miješalicama i bez statičkih miješalica, te kako bismo vidjeli je li njihovim korištenjem postignuta bolja konverzija u odnosu na šaržnu fotokemijsku sintezu. Za utvrđivanje prisutnosti fotoprodukata nakon provedenih reakcija korištene su tankoslojna kromatografija i tekućinska kromatografija vrlo visoke učinkovitosti. Rezultati dobiveni provođenjem fotokemijskih reakcija ukazuju da je najveće pseudoiskorištenje reakcije postignuto nakon 2 sata provođenja iste u reaktoru s pregradama, odnosno za uzorak 3-preg-2h(I2) i iznosi 21,15 %, dok je najmanje pseudoiskorištenje nakon 2 sata provođenja reakcije postignuto u praznom reaktoru, odnosno za uzorak 3-praz-2h(I2) i iznosi 6,69 %. Uz to, provođenjem fotokemijskih reakcija kod uzoraka 3-praz-1h(I2), 3-praz-2h(I2), 3-stup-1h(I2) i 3-stup-2h(I2), ciljani produkt 4 nastaje u relativno niskom iskorištenju, dok kod uzoraka 3-senz-e-1h i 3-senz-e-2h nastaje nešto više sporednih produkata u odnosu na glavni produkt. Ovi rezultati upućuju na činjenicu da je miješanje vjerojatno najintenzivnije u reaktoru s pregradama. Osim toga, veća iskorištenja u slučaju reaktora smanjenog volumena upućuju na činjenicu da tanji sloj kroz koji svjetlost prolazi tijekom reakcije ima značajan utjecaj na iskorištenje, ali isto tako da i materijal kroz koji svjetlost prolazi, što je kod ovog reaktora polimer, može imati značajan utjecaj na iskorištenje. |
| Abstract (english) | Additive manufacturing (AM) represents a set of processes that enable the creation of objects based on a computer 3D model by applying particles in thin layers, layer by layer. The additive manufacturing technologies used in this work are fused filament fabrication (FFF), stereolithography (SLA), and digital light processing (DLP). The first goal of this work was to use FFF, SLA, and DLP technologies on 3D printers to create test plates from transparent materials to determine the most suitable material for 3D printing of reactors in which photochemical reactions would be conducted for 2 hours. The computer-aided design (CAD) software Fusion 360 was used to create the test plate models, followed by 3D printing of the same. Using FFF technology, models of plates were made from polypropylene (PP) and polyethylene terephthalate glycol (PETG), while SLA technology produced models from polyacrylate, and DLP technology produced models from a mixture of polyacrylate and epoxy. Additionally, the materials used in SLA and DLP additive manufacturing technologies undergo post-processing, or a subsequent curing process lasting 5 and 15 minutes. Properties of the polymers used to create the plates were tested using a swelling test in the acetonitrile solvent. The results indicate that the degree of swelling of the sample is greater if the post-curing time is shorter. After conducting the test and considering the degree of swelling, it was concluded that the High Temp resin is suitable for printing reactors because it has the lowest swelling degree after 4 hours, amounting to 3.2 %. Additionally, the aim of this work was to conduct photochemical reactions in the Luzchem CCP-ICH2 reactor for a duration of 2 hours at a wavelength of 313 nm. For conducting photochemical reactions, reactors with static mixers and reactors without static mixers were used. The CAD program Fusion 360 was used to create the reactors, followed by 3D printing of the same. The reactors were then subjected to post-processing for 5 minutes. The photochemical reactions were conducted to see if there is a difference in the obtained products when using reactors with static mixers versus without static mixers, and to see if better conversion is achieved compared to batch photochemical synthesis. Thin-layer chromatography and ultra-high-performance liquid chromatography were used to determine the presence of photoproducts after the reactions. The results obtained from conducting photochemical reactions indicate that the highest reaction pseudo-yield of the reaction was achieved after 2 hours of conducting it ina reactor with partitions, specifically for the sample 3-preg-2h(I2) and amounts to 21,15 %, while the lowest pseudo-yield was achieved after 2 hours of conducting the reaction in an empty reactor, specifically for the sample 3-praz-2h(I2) and amounts to only 6.69 %. Additionally, conducting photochemical reactions for samples 3-praz-1h(I2),
3-praz-2h(I2), 3-stup-1h(I2) and 3-stup-2h(I2), the target product 4 is produced in relatively low yields, whereas for samples 3-senz-e-1h and 3-senz-e-2h somewhat more by-products are formed in relation to the main product. These results indicate that mixing is probably most intense in the reactor with partitions. Furthermore, highter yields in the case of a reduced volume reactor indicate that a thiner layer through which light passes during the reaction has a significant impact of the yield, but aldso that the material through which light passes, which is a polymer in this reactor, cas also have a significant impact of the yield. |
