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204 Pages·2008·8.36 MB·English

SYNTHESIS AND CHARACTERIZATION OF COPOLYMERS OF
DIISOCYANATES AND DIALCOHOL

A THESIS SUBMITTED TO
THE GRADUATE SCHOOL OF NATURAL AND APPLIED SCIENCES
OF
MIDDLE EAST TECHNICAL UNIVERSITY

BY

SELDA KESKİN

IN PARTIAL FULFILLMENT OF THE REQUIREMENTS
FOR
THE DEGREE OF DOCTOR OF PHILOSOPHY
IN
POLYMER SCIENCE AND TECHNOLOGY

SEPTEMBER 2008
Approval of the thesis:

SYNTHESIS AND CHARACTERIZATION OF COPOLYMERS OF
DIISOCYANATES AND DIALCOHOL

submitted by SELDA KESKİN in partial fulfillment of the requirements for
the degree of Doctor of Philosophy in Polymer Science and Technology
Department, Middle East Technical University by,

Prof. Dr. Canan Özgen
Dean, Graduate School of Natural and Applied Sciences

Prof. Dr. Cevdet Kaynak
Head of Department, Polymer Science and TechnologyDept., METU

Prof. Dr. Ali Usanmaz
Supervisor, Chemistry Dept., METU

Examining Committee Members :

Prof. Dr. Kemal Alyürük
Chemistry Dept., METU

Prof. Dr. Ali Usanmaz
Chemistry Dept., METU

Prof. Dr. Arife Doğan
Prosthodontics Dept., Gazi University

Prof. Dr Duygu Kısakürek
Chemistry Dept., METU

Assoc. Prof. Dr. Hasan Nur Testereci
Chemistry Dept., Kırıkkale University

Date :
I hereby declare that all information in this document has been obtained
and presented in accordance with academic rules and ethical conduct. I
also declare that, as required by these rules and conduct, I have fully cited
and referenced all material and results that are not original to this work.

Name, Last Name : Selda Keskin
Signature :

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ABSTRACT

SYNTHESIS AND CHARACTERIZATION OF COPOLYMERS OF
DIISOCYANATES AND DIALCOHOL

Keskin, Selda
Ph.D., Department of Polymer Science and Technology
Supervisor: Prof. Dr. Ali Usanmaz

September 2008, 184 pages

This study was aimed to synthesize low molecular weight hydroxyl terminated
polyurethane acrylate polymers that can be used in biomedical applications.
Acrylate end capping via inter-esterification reaction was successfully achieved
with the methacryloyl chloride addition to the hydroxyl ends of the
polyurethane at low temperatures. Isocyanate terminated polyurethane
acrylates were also synthesized for the sake of comparison. TDI, HDI and MDI
were used as diisocyanates for urethane synthesis and they were end capped
with MMA and HEMA. Nature of the monomers used had an effect on
thermal, morphological, and rheological properties that were interpreted in
terms of the level of hydrogen bonding and degree of phase separation.
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Synthesized polymers were characterized by NMR, FTIR-ATR, DSC, TGA,
GPC, Mass Spectroscopy, SEM and rheometry.

In the literature, polyurethane acrylate polymers have been synthesized from
the isocyanate terminated polyurethanes in which the urethane chains were
ended with isocyanate groups. However, the toxicity of the isocyanate groups
limited their biomedical applications especially in prosthetic dentistry as a soft
lining material. Therefore, it is inevitable to explore the cytotoxicity of
polyurethane acrylate polymers. For this purpose, silver nanoparticles that have
an average particle size of 40 nm, were incorporated to the synthesized
polymers. This addition, which intends to improve the degree of cytotoxicity,
was successful to a certain extent.

Keywords: Polyurethane, acrylate end capping, biocompatibility, silver
nanoparticle.

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ÖZ

DİİZOSİYANAT VE DİALKOL KOPOLİMER SENTEZİ VE
KARAKTERİZASYONU

Keskin, Selda
Doktora, Polimer Bilimi ve Teknolojisi Bölümü
Tez Yöneticisi: Prof. Dr. Ali Usanmaz

Eylül 2008, 184 sayfa

Bu çalışma, biyomedikal uygulamalarda kullanılabilecek düşük molekül
ağırlıklı hidroksil sonlu poliüretan akrilat polimerlerini sentezlemeyi
amaçlamıştır. İnter-esterleşme reaksiyonu ile düşük sıcaklıkta metakriloil
klorürün hidroksil sonlu poliüretana eklemesiyle akrilat sonlanması başarılı bir
şekilde gerçekleştirilmiştir. İzosiyanat sonlu poliüretan akrilatlar da
karşılaştırma amacıyla sentezlenmiştir. TDI, HDI ve MDI, üretan sentezinde
kullanılan diizosiyanatlardır ve akrilat sonlandırması MMA ve HEMA
kullanılarak yapılmıştır. Kullanılan monomerlerin ısıl, morfolojik ve reolojik
özelliklere etkisi hidrojen bağının seviyesine ve faz ayrım derecesine göre
değerlendirilmiştir. Elde edilen polimerler NMR, FTIR-ATR, DSC, TGA,
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GPC, Kütle Spektrometresi, SEM ve reometre analizleriyle karakterize
edilmiştir.

Literatürde poliüretan akrilat polimerleri, zincir sonları izosiyanat gruplarıyla
sonlanmış poliüretanlardan sentezlenmektedir. İzosiyanat gruplarının
toksisitesi, bu poliüretanların özellikle protetik diş hekimliğinde yumuşak astar
malzemesi olarak kullanılmalarını sınırlandırmıştır. Bu nedenle poliüretan
akrilat polimerlerinin sitotoksisite özelliklerinin araştırılması kaçınılmaz
olmuştur. Bu amaçla, ortalama parçacık boyutu 40 nm olan gümüş nano
parçacıkları sentezlenen polimerlere eklenmiştir. Sitotoksisiteyi iyileştirmeyi
amaçlayan bu ekleme belirli oranda etkili olmuştur.

Anahtar Kelimeler : Poliüretan, akrilat eklemesi, biyouyumluluk, gümüş
nanopartikül.

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To my mother
and
To the memory of my father

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ACKNOWLEDGEMENTS

I would like to express my deepest gratitude to my supervisor Prof. Dr. Ali
Usanmaz for his support, encouragement, and guidance throughout the study. I
am grateful to Prof. Dr. Arife Doğan for her encouragement, and advice
throughout the research. She provided not only the necessary guidance, but
also expanded my knowledge in many areas especially in dentistry.

I would like to thank to my friend and colleague Dr. Kemal Behlülgil for his
suggestions, comments and valuable contributions throughout the study and I
am thankful to my friend Binnur Özkan for her moral support and help during
this research. Special appreciation is due to my dear friend Serhan Demirci for
his moral support, continuous encouragement, personal advices and his support
on the graphics.

I would like to express my appreciation to Prof. Dr. Çiğdem Erçelebi and Prof.
Dr. Hayrettin Yücel for their understanding and support throughout the study
and during the period of writing of my thesis. I am also grateful to METU
Central Laboratory research associates and staff. Especially worth mentioning
are the contributions from the following individuals: Elif Kemeröz, Dr. Elif
Tarhan Bor, Assoc. Prof. Necati Özkan, Leyla Molu, Seda Bilgi, Sedat Canlı,
Dr. Burcu Akata Kurç, Dr. İbrahim Çam.

Help of my lab mates, Elif Vargün, Bengi Aran, Selin Kozanoğlu, and Şule
Altınsoy are gratefully acknowledged.

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I would also like to thank Şükran Yılmaz from ŞAP Institute for the
cytotoxicity analysis. I also want to thank to my friends Yusuf Nur for the mass
spectroscopy analysis, Dr. Ertuğrul Sahmetlioğlu for the GPC analysis and Dr.
Seha Tirkeş for his help and valuable discussions during this work.

I am truly in debt to my mother for her endless support, understanding, and
belief in me.

This study was supported by the Scientific and Research Council of Turkey
(TÜBİTAK) Grant No: 104T424.

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