WSEAS Transactions on Biology and Biomedicine

Print ISSN: 1109-9518
E-ISSN: 2224-2902

Volume 14, 2017

Notice: As of 2014 and for the forthcoming years, the publication frequency/periodicity of WSEAS Journals is adapted to the 'continuously updated' model. What this means is that instead of being separated into issues, new papers will be added on a continuous basis, allowing a more regular flow and shorter publication times. The papers will appear in reverse order, therefore the most recent one will be on top.

Grafted Copolymer Based on Chitosan and Poly(N-Isopropylacryl Amide) via Click Technique. I. Synthesis and Characterization

AUTHORS: Catalina Natalia Cheaburu-Yilmaz, Sinem Yaprak Karavana, Onur Yilmaz

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ABSTRACT: As chitosan’s solubility represents a drawback for further applications, the functionalization of chitosan became attractive by a variety of chemical methods. The present study deals with the chemical modification of chitosan by using click chemistry technique as versatile tool being easy to perform with high yields and no additional by products. The approach used herein was to attach a responsive moiety (e.g. NIPAAm, HEMA or DMAEMA) on the macromolecular chain of chitosan via an azide-alkyne coupled reaction. More specifically, the reaction occurred between azide-chitosan and alkyne terminated responsive polymer. The method includes the modification of chain transfer agent with alkyne terminated groups, polymerization of responsive monomer, azidation steps of chitosan and final click reaction between two end products. Structure of end products and intermediaries were confirmed by the FT-IR and H-NMR spectra. Thermal characterization was performed showing different thermal behavior with the chemical modification. As main outcome, chitosan-g-PNIPAAm was obtained, the structure being confirmed by the disappearance of azide group and the presence of triazole moiety within the final product. The new approach of advancing the reaction via alkyne terminated-PNIPAAm, synthesized by RAFT, seemed to be successful as verified by 1H-NMR. Thermal properties revealed a better thermal stability for the new polymeric materials as the structure was more complex.

KEYWORDS: Click chemistry, Chitosan, Phthaloylation, PNIPAAm, Alkyne terminated PNIPAAm, Triazole ring, Graft copolymer


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WSEAS Transactions on Biology and Biomedicine, ISSN / E-ISSN: 1109-9518 / 2224-2902, Volume 14, 2017, Art. #17, pp. 120-128

Copyright © 2017 Author(s) retain the copyright of this article. This article is published under the terms of the Creative Commons Attribution License 4.0

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