Makroporozna Al[spodaj]2O[spodaj]3 keramika iz polimernih kompozitov-sinteza in katalitske lastnost

diplomsko delo univerzitetnega študijskega programa I. stopnje

Nina Štajnfelzer (Author), Amadeja Koler (Mentor), Peter Krajnc (Co-mentor)

Abstract

V diplomskem delu smo se osredotočili na sintezo poroznih kompozitnih materialov, ki združujejo večfunkcionalne akrilate in delce aluminijevega oksida (Al₂O₃). Namen raziskave je bil pridobiti visoko porozen kompozitni material z nadzorovano velikostjo in obliko por ter s sintranjem le tega izdelati porozno keramiko za potencialno uporabo kot trdni nosilec za katalizatorje. Sintezo smo izvedli s fotopolimerizacijo kontinuirne faze emulzije z visokim deležem notranje faze, kjer je zunanja faza, ki je vsebovala akrilatne monomere in delce Al₂O₃, tvorila osnovo kopozitnega materiala. Preučevali smo vpliv različnih monomerov, topil in surfaktantov na stabilnost in morfologijo visoko poroznih kompozitov z odprto celično strukturo in možnost priprave porozne keramike-direktno s sintranjem pripravljenih kompozitnih materialov. Morfologijo kompozitov in keramike na osnovi Al₂O₃ smo okarakterizirali z vrstično elektronsko mikroskopijo (SEM). Iz SEM posnetkov je razvidno, da smo pridobili odprto porozne kompozitne materiale, s primarnimi porami velikosti okoli 20 µm v primeru kompozitov Sartomer 492/Al2O3. Z eksperimenti adsorpcije/desorpcije dušika z uporabo BET metode smo izmerili nizke specifične površine (do 2 m²/g), ki smo jih izboljšali s polimerizacijo 6-funkcionalnega dipentaeritritol heksaakrilata (DPHA) in 5-funkcionalnega pentaeritritol tetraakrilata (PETA). Kompozitni materiali pripravljeni s polimerizacijo 6-funkcionalnega akrilata, so izkazali povišano BET specifično površino (7 m²/g) in pa slabše definirano odprto celično strukturo. S kopolimerizacijo DPHA ali PETA z metil metakrilatom (MMA) se odprtocelična struktura kompozitov poruši. Kompozite z odprto porozno celično morfologijo smo sintrali, kar je privedlo do nastanka poroznega keramičnega materiala na osnovi Al₂O₃ z enako morfologijo kot polimerni kompozitni prekurzorji.

Keywords

porozna keramika;poliHIPE;aluminijev oksid;sintranje;porozni kompozitni materiali;diplomske naloge;

Data

Language:	Slovenian
Year of publishing:	2024
Typology:	2.11 - Undergraduate Thesis
Organization:	UM FKKT - Faculty of Chemistry and Chemical Engineering
Publisher:	[N. Štajnfelzer]
UDC:	663.3-127(043.2)
COBISS:	217044995
Views:	32
Downloads:	17
Average score:	0 (0 votes)
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Other data

Secondary language:	English
Secondary title:	Macroporous Al₂O₃ ceramics from polymer composites-synthesis and catalytic properties
Secondary abstract:	In the thesis, the focus was placed on the synthesis of porous composite materials that combine multifunctional acrylates and aluminum oxide (Al₂O₃) particles. The aim of the research was to obtain a highly porous composite material with controlled pore size and shape, and by sintering this material, to produce a porous ceramic for potential use as a solid catalyst support. The synthesis was carried out by photopolymerization of a high internal phase emulsion, where the external phase, containing acrylate monomers and Al₂O₃ particles, formed the basis of the composite material. The influence of different monomers, solvents, and surfactants on the stability and morphology of highly porous composites with an open cellular structure, as well as the possibility of preparing porous ceramics directly by sintering the prepared composite materials, was studied. The morphology of the composites and Al₂O₃-based ceramics was characterized using scanning electron microscopy (SEM). From the SEM images, it was observed that open-porous composite materials with primary pores of around 20 µm were obtained in the case of Sartomer 492/Al₂O₃ composites. Low specific surface areas (up to 2 m²/g) were measured using nitrogen adsorption/desorption experiments with the BET method, which were improved by the polymerization of 6-functional dipentaerythritol hexaacrylate (DPHA) and 5-functional pentaerythritol tetraacrylate (PETA). Composite materials prepared by polymerization of the 6-functional acrylate showed an increased BET specific surface area (7 m²/g) but a less defined open cellular structure. The open-cell structure of the composites was disrupted by copolymerization of DPHA or PETA with methyl methacrylate (MMA). Composites with an open porous cellular morphology were sintered, leading to the formation of a porous ceramic material based on Al₂O₃ with the same morphology as the polymer composite precursors.
Secondary keywords:	porous ceramic;polyHIPE;aluminum oxide;sintering;porous composite materials;
Type (COBISS):	Bachelor thesis/paper
Thesis comment:	Univ. v Mariboru, Fak. za kemijo in kemijsko tehnologijo
Pages:	1 spletni vir (1 datoteka PDF (VIII, 43 f.))
ID:	24873022