Title
Synthesis and characterization of new pH- and thermo-responsive hydrogels based on N-isopropylacrylamide and 2-oxazolines
Date Issued
03 April 2014
Access level
open access
Resource Type
journal article
Author(s)
Publisher(s)
Taylor & Francis
Abstract
New pH- and thermo-responsive hydrogels (HG) were synthesized by free radical polymerization of N-isopropylacrylamide and a macromonomer, which was a hydrolyzed random copolymer of 2-carboxyethyl- and 2-methyl-2-oxazoline, using a bisacrylamide as crosslinker. The polymerization was carried out in a mixture of water and ethanol at room temperature and was initiated by ammonium peroxodisulfate. The HG showed conformational transitions with variation of temperature and/or pH-value and as a function of hydrogel composition. This property was shown macroscopically as hydrogel contraction or expansion. The HG structures were characterized by high-resolution magic angle spinning (HRMAS) NMR spectroscopy. The thermal properties, in particular the lower critical solution temperatures, were determined by temperature-dependent HRMAS NMR measurements and differential scanning calorimetry. The pH responsibility was determined by swelling experiments in water at different pH values. © 2013 Taylor & Francis.
Start page
208
End page
216
Volume
17
Issue
3
Language
English
OCDE Knowledge area
Ingeniería química
Química
Subjects
Publication version
Version of Record
Scopus EID
2-s2.0-84887475122
Source
Designed Monomers and Polymers
ISSN of the container
1568-5551
Sponsor(s)
The authors wish to thank the Academic Department of Research (DGI) of Pontifical Catholic University of Peru for the financial support for this research. The assistance of Dr M Edelmann in the DSC studies and A Korwitz in NMR measurements is gratefully acknowledged.
Sources of information:
Directorio de Producción Científica
Scopus