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Sa svrhom ispitivanja kopolimerizacijskih reaktivnosti provedene su terpolimerizacije tert-butilaminoetil-metakrilata (TBAEMA), oktadecil-metakrilata (ODMA) i metil-metakrilata (MMA) te TBAEMA, ODMA i stirena (St). Navedeni materijali potencijalno su primjenjivi kao reološki modifikatori u industriji maziva. Reakcije su provedene do niskih konverzija (< 10 mas. %) uz peroksidni inicijator pri temperaturi od 70 °C u dilatometru volumena oko 20 mL i uz ukupnu koncentraciju monomera u toluenu od 2 mol dm^-3. Na oba ternarna sustava ispitan je dizajn optimalnih eksperimenata prema kojemu je za potpuni opis terpolimerizacijskog sustava (međuovisnosti sastava smjese monomera i sastava terpolimera) dovoljno provesti samo tri eksperimenta pri čemu se udjeli monomera u pojedinoj reakcijskoj smjesi mijenjaju tako da jedan monomer ima udio 80 mol. %, a druga dva po 10 mol. %. Za predviđanje sastava polimera korišteni su omjeri kopolimerizacijskih reaktivnosti pripadajućih binarnih smjesa određeni u prijašnjim istraživanjima na Zavodu za tehnologiju nafte i petrokemiju Fakulteta kemijskog inženjerstva i tehnologije. Stvarni sastav sintetiziranih terpolimera određen je nuklearnom magnetskom rezonancijom (NMR). Toplinska stabilnost dobivenih terpolimera ispitana je termogravimetrijskom analizom. With the purpose of determining copolymerization reactivity ratios, terpolymerizations of 2-(tert-butylamino)ethyl methacrylate (TBAEMA), octadecyl methacrylate (ODMA), and methyl methacrylate (MMA) as well as that of TBAEMA, ODMA and styrene (St) have been conducted. The reactions were carried out with a peroxide initiator at 70 °C in a 20 mL dilatometer with total monomer concentration of 2 mol dm^-3 in toluene and terminated at low conversions (< 10 wt %). For both ternary systems the optimal experiment design was studied, according to which for a complete description of the terpolymer system (the interdependence of the composition of the monomer mixture and the composition of the terpolymer) only three experiments need to be performed, with alternating the monomer concentrations in each reaction mixture so that one monomer has a portion of 80 mol %, with the other two having 10 mol %. Copolymerization reactivity ratios of the corresponding binary mixtures were obtained from past research on Petroleum and Petrochemical Department, Faculty of Chemical Engineering and Technology, University of Zagreb, and used to predict the composition of terpolymers. Actual composition of synthesized terpolymers was determined from nuclear magnetic resonance (NMR) spectrums. Thermal stability of terpolymers was examined using thermogravimetric analysis (TGA).

Proceedings contains articles presented at Conference divided into sections: open lecture (1), chemical analysis and synthesis (3), chemical and biochemical engineering (8), food technology and biotechnology (8), medical chemistry and pharmacy (3), environmental protection (11) and meeting of young chemists (2).

Veliki zahtjevi na ograničene svjetske sirovine potakli su razvoj kružne ekonomije. To je koncept prema kojem bi se proizvodi osmišljavali tako da budu dio vrijednosne mreže unutar koje bi ponovna uporaba i prenamjena proizvoda i materijala zajamčila trajnu reciklažu resursa. Europska unija potiče takav pametan i održiv razvoj, a recikliranje otpadnih jestivih ulja odlično se uklapa cijeli koncept. Za sintezu biodizela korišteno je otpadno restoransko ulje za koje je pokazano da ima iznimnu kvalitetu s obzirom na ključne parametre, n-butanol i N,N',N''-tris(3-dimetilamino)propil gvanidin (GV3) kao katalizator. Prednost novih gvanidinskih katalizatora je visoka aktivnost i izbjegavanje nepoželjnih procesa saponifikacije koji postoje kod konvencionalnih baznih katalizatora. Provedena su preliminarna ispitivanja u kojima je odabran n-butanol nad izo-butanolom. Također, određeni su značajni reakcijski parametri čije utjecaje na reakciju treba istražiti. Značajni parametri su temperatura, vrijeme reakcije, molarni omjer butanola i ulja i maseni udio katalizatora. Odziv procesa je konverzija otpadnog biljnog ulja u produkte. Određeno je i radno područje unutar kojeg će se ispitivanja vršiti i s tim je radnim područjem, pomoću programskog paketa Design Expert, izrađen Box-Behnken plan pokusa s četiri parametra koji se variraju na tri razine. Pokusi su izvršeni prema planu pokusa i rezultati su analizirani metodom 1H NMR. Na temelju rezultata pokusa, metodom odzivnih površina (RMS), dobiven je empirijski model unutar kojeg je za bilo koju kombinaciju ulaznih faktora (T, t, wkat i molarni omjer A/U) moguće predvidjeti odziv procesa, konverziju Xm. Valjanost modela provjerena je kroz različite funkcije cilja u kojima je zahtijevana visoka konverzija uz uštedu katalizatora i/ili butanola. Dobiveni optimalni parametri za jednu od funkcija cilja su: temperatura 40,5 °C, vrijeme 30 min, molarni omjer reaktanata od 9,82 mol/mol i maseni udio katalizatora 1,38 % uz predviđenu konverziju od 92,4 %. U tom je pokusu ostvarena konverzija 84,9 %. Great demands on worlds limited supplies of raw materials have induced the development of circular economy. It is a concept by which products would be made to be a part of a network in which reuse and redevelopment of products and materials would guarantee permanent recycling of resources. European Union encourages that sort of smart and sustainable development, and recycling of waste vegetable oils fits perfectly in that concept. Waste restaurant oil, that has exceptional quality in terms of key parameters, n-butanol and N,N',N''-tris(3-dimethylamino)propyl guanidine (GV3) as a catalyst have been used for biodiesel production. Advantage of novel guanidine catalysts is their high activity and avoiding undesirable saponification that happens when using conventional base catalysts. In preliminary tests n-butanol was chosen over iso-butanol. Also, important reaction parameters, whose influence should be estimated, were determined. Important parameters are reaction temperature, reaction time, butanol to oil ratio and mass share of catalyst. Response of the process is the conversion of waste vegetable oil into products. Operating range has been determined, and with that operating range, using program package Design Expert, a Box-Behnken design of experiments has been made with four parameters varied on three levels. Experiments were executed according to the design of experiments and results have been analyzed with 1H NMR method. Using the results, with response surface methodology (RMS), an empirical model has been made and with it, it is possible to predict the process response (conversion Xm) for any combination of input parameters (T, t, wkat and molar ratio A/U). Validation of the model has been made with different objective functions where a high conversion rate has been demanded with minimizing the catalyst mass share and/or minimizing butanol to oil ratio. Optimal parameters for one of objective functions are: temperature 40.5 °C, time 30 min, butanol to oil ratio 9.82 mol/mol and mass share of catalyst 1.38 % with predicted conversion rate of 92.4 %. Conversion for that experiment was determined to be 84.9 %.