Hostname: page-component-8448b6f56d-42gr6 Total loading time: 0 Render date: 2024-04-24T10:07:59.077Z Has data issue: false hasContentIssue false

Molecular relaxation in Chitosan films in GHz frequency range

Published online by Cambridge University Press:  10 February 2014

Siva Kumar-Krishnan
Affiliation:
CINVESTAV-Queretaro, Libramiento Norponiente 2000, Queretaro, QRO 76230, MEXICO
Evgen Prokhorov
Affiliation:
CINVESTAV-Queretaro, Libramiento Norponiente 2000, Queretaro, QRO 76230, MEXICO
Gabriel Luna-Barcenas
Affiliation:
CINVESTAV-Queretaro, Libramiento Norponiente 2000, Queretaro, QRO 76230, MEXICO
Get access

Abstract

The molecular relaxations behavior of chitosan (CS) films in the wide frequency range of 0.1-3x109 Hz (by using three different impedance analyzers) have been investigated in the temperature range of -100C to 120°C using Dielectric Spectroscopy (DS). Additionally to the low frequency molecular relaxations such as α and β relaxations, for the first time, high frequency (1-3 GHz) relaxation process has been observed in the chitosan films. This relaxation exhibits Arrhenius-type dependence in the temperature range of -100 C to 54°C with negative activation energy -2.7 kJ/mol. At temperatures above 54°C, the activation energy changes from -2.7 kJ/mol to +4.4 kJ/mol. Upon cooling, the activation energy becomes negative again with a value of -1.2 kJ/mol. The bound water between chitosan molecules strongly modifies molecular motion and the relaxation spectrum, giving rise to a new relaxation at the frequency at ca. 1 GHz. In situ FTIR analysis has shown that this relaxation related to the changes in vibration of the –OH, NH and –CO functional groups.

Type
Articles
Copyright
Copyright © Materials Research Society 2014 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Gonzalez-Campos, J.B., Prokhorov, E., Luna Barcenas, G., Mendoza-Galvan, A., Sanchez, I.C., Nuno-Donlucas, S.M., Garcia-Gaitan, B., Kovalenko, Y., J. Polym Sci. Part B: Polym Phys. 47, 22592271 (2009).CrossRefGoogle Scholar
Kobaisi, M. Al, Murugaraj, P., Mainwaring, D.E., J. Polym Sci Part B: Polym Phys. 50, 403414 (2012).CrossRefGoogle Scholar
Viciosa, M.T., Dionisio, M., Mano, J.F., Biopolymer 81, 149159 (2006).CrossRefGoogle Scholar
Fukuda, T., Takada, A., Miyamoto, T., In Cellulosic Polymers, Blends and Composites; Gilbert, RD, Ed, Hanser: New York (1994).Google Scholar
Montes, H., Mazeau, K., Cavaille, J.Y., Macromolecules 30, 69776984 (1997).CrossRefGoogle Scholar
Nogales, A., Ezquerra, T.A., Rueda, D.R., Retuert, M., J. Colloid Polym Sci. 275, 419425 (1997).CrossRefGoogle Scholar
Radloff, D., Boeffel, C., Spiess, H.W., Macromolecules 29, 15281534 (1996).CrossRefGoogle Scholar
Butler, M.F., Cameron, R.E., Polymer 41, 22492263 (2000).CrossRefGoogle Scholar
Maissner, D., Einfeldt, J., Wasniewski, A.K., J. Non- Cryst. Solids 320, 4055 (2003).Google Scholar
Einfeldt, J., Maissner, D., Kwasniewski, A., Prog. Polym. Sci. 26, 14191472 (2001).CrossRefGoogle Scholar
Harvey, S.C., Hoekstra, P., J. Phys. Chem. 76, 29872993 (1972).CrossRefGoogle Scholar
Rrey, W.S., Evans, J.T.E., Hitzrot, L.H., J. Colloid and Interface Sci. 26, 306316 (1968).Google Scholar
Marzec, E., Kubisz, L., Jaroszyk, F., Int. J. Biological Macromolecules 18, 2731 (1996).CrossRefGoogle Scholar
Hoekstra, P., Doyle, W.T., J. Colloid and Interface Sci. 36, 513521(1970).CrossRefGoogle Scholar
Murugaraj, P., Mainwaring, D.E., Tonkin, D.C., Kobaisi, M. Al, J. Appl. Polymer Sci. 120, 13071315 (2011).CrossRefGoogle Scholar
Noriega, E.S., Subramanian, A., Int. J. Carbohydrate Chem. 2011, 11551168 (2011).CrossRefGoogle Scholar
Zawadzki, J., Kaczmarek, H., Carbohydrate Polymers 80, 394400 (2010).CrossRefGoogle Scholar