Oksalati, imobilizirani na vinilbenzil kloridni nosilec

magistrsko delo študijskega programa II. stopnje

Selena Bošnjak (Author), Jernej Iskra (Mentor), Peter Krajnc (Co-mentor)

Abstract

V magistrskem delu smo želeli sintetizirati oksalatne estre vezane na polimerni nosilec poli(vinilbenzil klorid-ko-divinil benzen). Oksalati namreč pri reakciji z vodikovim peroksidom in ob prisotnosti občutljivca, tvorijo visoko-energijsko molekulo, ki se pretvori v osnovno stanje s sevanjem svetlobe. Ta reakcija je izredno zanimiva za morebitno detekcijo vodikovega peroksida. Za želen rezultat smo morali najprej uvesti alkoholne skupine, preko katerih smo nato vezali oksalat. Začeli smo s pripravo monolita poli(VBC-ko-DVB) z radikalsko polimerizacijo. Nastali monolit je imel specifično BET površino relativno nizko – 5,2 m2/g. Želeli smo polimer v hiperzamreženi obliki, saj bi tako dobili precej večjo specifično BET površino, kar smo dosegli s polimerizacijo emulzije z visokim deležem notranje faze (poliHIPE). Reakcija je bila uspešna, saj je površina narasla na kar 796,5 m2/g. Preostala vinil kloridna skupina, ki ni reagirala v reakciji hiperzamreženja, je služila v nadaljnji reakciji za vezavo 2-amino-2-hidroksimetil-propan-1,3-diol alkoholne skupine. Reakcija je potekala 24 ur na povišani temperaturi – 90 °C v dušikovi atmosferi. BET specifična površina se je zmanjšala na 512,8 m2/g, kar pa je vendarle, v primerjavi z osnovnim monolitom, precej več. Sledila je vezava oksalata na polimer in nato še reakcija s pentafluorofenolom, s čim smo uvedli fenolno skupino z elektron privlačnimi fluorovimi atomi. Največjo težavo nam je povzročala reakcija z oksalil kloridom oz. uvedba oksalne skupine na polimer, saj je reakcija zelo agresivna in nam je porušila morfologijo polimera – BET površina je bila 6,4 m2/g, kar je primerljivo z začetno površino osnovnega monolita. Tukaj smo zato poskusili z različno temperaturo – iz 80 °C smo temperaturo spremenili na sobno temperaturo, vendar pa izboljšanja s polimerno strukturo ni bilo. Nato smo naredili reakcijo še z različno količino reagenta – 5 ekvivalentov oksalil klorida in 1 ekvivalent oksalil klorida. 5 ekvivalentov oksalil klorida je ponovno porušilo polimerno strukturo, medtem ko je 1 ekvivalent oksalil klorida uspešno ohranil strukturo in BET specifična površina je znašala 448,2 m²/g. Toda FTIR spekter je pokazal, da je 1 ekvivalent oksalil klorida premala količina, da bi reakcija potekla v tolikšni meri kot smo pričakovali. Reakcija s pentafluorofenolom, ki je potekla na sobni temperaturi, je nato nazaj zamrežila polimer, vendar pa ne moremo vedeti ali je struktura enaka kot pred reakcijo z oksalil kloridom. Na koncu smo na polimeru opravili še reakcijo kemiluminiscence, pred katero smo najprej testirali v katerem topilu sintetiziran polimerni material nabreka.

Keywords

polimerni nosilci;poliHIPE;kemiluminiscenca;oksalat;vodikov peroksid;magistrske naloge;

Data

Language:	Slovenian
Year of publishing:	2016
Typology:	2.09 - Master's Thesis
Organization:	UM FKKT - Faculty of Chemistry and Chemical Engineering
Publisher:	[S. Bošnjak]
UDC:	547.461.2:544.431.7.057:535.379(043.2)
COBISS:	20346902
Views:	1367
Downloads:	117
Average score:	0 (0 votes)
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Other data

Secondary language:	English
Secondary title:	OXALATES IMMOBILIZED ONTO VINYLBENZYL CHLORIDE POLYMER SUPPORTS
Secondary abstract:	In this master’s thesis, we wanted to synthesize an oxalate ester bonded to a polymeric carrier poly (vinylbenzyl chloride-co-divinyl benzene). When reacting with hydrogen peroxide and in the presence of fluorophore, oxalates form a high-energy molecule, which is converted into its basic state by light radiation. This reaction is very interesting because of the possible detection of hydrogen peroxide. For the desired result, we firstly needed to introduce the alcohol groups, through which we then bind the oxalate. We began by preparing the monolith poly (VBC-co-DVB) with a radical polymerization. The resulting monolith had a relatively small specific BET surface area – 5,2 m2/g. We wanted to get a polymer in a hypercrosslinked form, since it would result in a much higher specific BET surface area. This was achieved by polymerizing the emulsion with a high proportion of the internal phase (polyHIPE). The reaction was successful, because the surface area increased to 796,5 m2/g. The residual vinyl chloride group, which did not react in the reaction of hypercrosslinking, was used in the subsequent reaction for the binding of 2-amino-2-hydroxymethyl-propane-1,3-diol, the alcohol group. The reaction lasted for 24 hours at an elevated temperature - 90 °C in a nitrogen atmosphere. The BET specific surface area was reduced to 512,8 m2/g, which is, in comparison with the basic monolith, much more. Next up was binding the oxalate to the polymer and then the reaction with the pentafluorophenol, with which we introduced the phenolic group with electron attractive fluorine atoms. The biggest problem was the reaction with oxalyl chloride or the introduction of the oxalic groups on the polymer, as the reaction is very aggressive and it collapsed the polymer morphology – the BET surface area was 6,4 m2/g, which is comparable with the initial surface of the basic monolith. Here we tried varying the temperature - it was changed from 80 °C to room temperature, but the improvement of the polymer’s structure was not achieved. Then we made a further reaction with different amounts of a reagent - 5 equivalents of oxalyl chloride and 1 equivalent of oxalyl chloride. 5 equivalents of oxalyl chloride re-collapsed the polymeric structure, whereas 1 equivalent of oxalyl chloride successfully preserved the structure. The BET specific surface area was 448,2 m²/g, but the FTIR spectrum showed that 1 equivalent of oxalyl chloride was a too small amount in order for the reaction to meet our expectations. The reaction with pentafluorophenol, which occurred at room temperature, then cross-linked the polymer back, however we cannot know whether the structure is the same as prior to the reaction with the oxalyl chloride. Finally, we have conducted a chemiluminescence reaction on the polymer before which we tested in which solvent the synthesized polymer material swells.
Secondary keywords:	polymer supports;polyHIPE;chemiluminescence;oxalate;hydrogen peroxide;
URN:	URN:SI:UM:
Type (COBISS):	Master's thesis/paper
Thesis comment:	Univ. v Mariboru, Fak. za kemijo in kemijsko tehnologijo
Pages:	X, 61 str.
ID:	9164839