Tez özetleri Astronomi ve Uzay Bilimleri Anabilim Dalı

The Synthesis of The Acrylamide Polymers Which Contain 2,3-Dimercaptosuccinic Acid End Groups and Investigation of Their Physichochemical Properties

KMnO4 and ceric salts form very effective redox systems in the presence of organic reducing agents such as alcohols, aldehydes and carboxylic acids.

In this work, by using 2, 3-dimercaptosuccinic acid-Ce(IV) and 2, 3-dimercaptosuccinic acid-KMnO4 redox systems, the free radical polymerization of acrylamide monomer was performed in acid-aqueous medium at low temperatures. Water soluble polyacrylamides containing 2, 3-dimercaptosuccinic acid end groups were synthesized. In experimental studies, the effects of mole ratio of acrylamide to initiator (nAAm/nCe(IV)), concentration of sulfuric acid, temperature and time on the yield and molecular weight of polymer were investigated.

It was observed that, the decrease of initiator concentration resulted in a decrease in the yield but an increase in molecular weight of polymer. The increase of reaction temperature resulted in a decrease in the yield but an increase in molecular weight of polymer. The increase of acid concentration led to an increase in the yield, but decrease in molecular weight of polymer. With increasing of polymerization time, the molecular weight of polymer didn’t change, but there was an increase in the yield.

Ce(IV) and Mn(VII) ions are reduced to Ce(III) and Mn(II) ions in the polymerization reactions. These ions can be absorbed by polymer containing DMSA end groups. The existence and amount of Ce(III) and Mn(II) ions bonded to polymer were examined by UV-visible spectrometric and atomic absorbtion measurements respectively. The particle size distributions of acrylamide polymers which were synthesized at different initiator concentrations (nAAm/nCe(IV))=20, 100, 250, 500), were investigated by photon correlation spectroscopy. The structures of the polyacrylamide, AAm and 2, 3-dimercaptosuccinic acid were examined by FT-IR spectrometry.

By using N,N´-methylene bis(acrylamide) as crosslinking agent and Ce(IV)-DMSA redox system, water-insoluble but water-swellable, acrylamide-N,N´-methylenebis(acrylamide) gels were synthesized. The effect of the parameters such as acid, initiator and crosslinker concentrations on the swelling behaviors of synthesized hydrogels in distilled water were examined. At a constant monomer concentration, swelling equilibrium ratios increased with a decresae in the sulfuric acid, initiator and crosslinker concentrations.

The effect of the crosslinker concentrations on the kinetic parameters were determined by using swelling-kinetic equations.

AVCI Filiz
Danışman : Prof.Dr.Cemil İBİŞ

Anabilim Dalı : Kimya

Programı : Organik Kimya

Mezuniyet Yılı : 2008

Tez Savunma Jürisi : Prof.Dr. Cemil İBİŞ

Prof.Dr. Süleyman TANYOLAÇ

Prof.Dr. F.Serpil GÖKSEL

Prof.Dr. Mustafa BULUT

Prof.Dr. Ayşe YUSUFOĞLU