%0 Journal Article
%T A Study of the Deformation, Network, and Aging of Polyethylene Oxide Films by Infrared Spectroscopy and Calorimetric Measurements
%A Carl Bergeron
%A Etienne Perrier
%A Aymeric Potier
%A Genevi豕ve Delmas
%J International Journal of Spectroscopy
%D 2012
%I Hindawi Publishing Corporation
%R 10.1155/2012/432046
%X The calorimetric and infrared (IR) spectroscopy measurements of polyethylene oxide (PEO) are used to evaluate the deformation and relaxation that films experience during a temperature cycle (30∼C每90∼C每30∼C). After melting, the intensity of some bands decreases by 10 to 70%. During the temperature cycle, the C每O band in the 1100ˋcmˋ1 region and the C每C每O deformation bands at 650 and 500ˋcmˋ1 show some new features. A network of cooperative oxygen-hydrogen interactions between the PEO chains form in films with special history, namely, in thermally treated films, in thin films prepared from gel forming solutions, and in thick films after aging. The interchain interaction network is suggested from the IR absorption bands in the 1200 and 900ˋcmˋ1 region and also from small bands at 1144 and 956ˋcmˋ1. The network seems absent or reduced in thin films. IR spectroscopy appears a sensitive technique to study chain conformations in PEO films and in other materials where order, disorder, and the formation of intermolecular interactions coexist. 1. Introduction The physico-chemical properties of pure polyethylenoxide (PEO) such as crystallinity [1每3], thermal properties [2, 3], and morphology [4, 5] have been investigated. The polar and nonpolar parts of the PEO sequence give rise to a wide range of properties unknown to polyolefins. An intriguing property of PEO in dilute and very dilute solutions is the formation of stable clusters [6, 7]. Nonequilibrium effects related to the polymer-solvent interactions have been studied [8]. Associations have been investigated by several techniques in order to understand the thermodynamics of their origin and obtain some insight into protein-water interactions [9]. The effect of shear on solutions and resulting degradation has been analysed [10]. The vibrational spectra of oriented PEO films have been measured [11, 12] and the positions of the bands were compared to those calculated. Structural models and comparison with the IR spectra of small molecules have suggested the assignments of the bands between 3000 and 400ˋcmˋ1 observed for the solid and for the melt. Ionic conductivity, effect of surface on conformations, and crystallinity have been investigated in PEO systems in fundamental and applied FTIR studies [13每16]. FTIR spectroscopy is used to study the specific interactions between the PEO chains and small molecules [13]. Chain-chain interactions in composites and chain-ion interactions leave a trace on the vibrational spectrum. They increase the parallel portion of the vibrations at the expanse of the perpendicular
%U http://www.hindawi.com/journals/ijs/2012/432046/