Dynamics of Water Absorbed in Polyamides
Laurati M, Sotta P, Long DR, Fillot LA, Arbe A, Alegria A, Embs JP, Unruh T, Schneider GJ, Colmenero J (2012)
Publication Status: Published
Publication Type: Journal article
Publication year: 2012
Journal
Publisher: AMER CHEMICAL SOC
Book Volume: 45
Pages Range: 1676-1687
Journal Issue: 3
DOI: 10.1021/ma202368x
Abstract
We investigate the dynamics of water absorbed in amorphous and semicrystalline aromatic polyamide copolymers. The combination of dielectric spectroscopy and quasi-elastic neutron scattering experiments allows us to characterize the water dynamics over a wide range of temperatures (dielectric spectroscopy) and at microscopic length scales (neutron scattering). The dielectric investigation evidences two relaxations associated with water motions: a fast process corresponding to motions of loosely bonded water molecules and a slower process corresponding to motions of amide-water complexes. While the slower process presents the characteristic Arrhenius temperature dependence of a secondary local relaxation over the whole temperature range, the fast process shows a crossover from Arrhenius to Vogel-Fulcher-Tamman (VFT) behavior at T approximate to 225 K, characteristic of confined water dynamics. The microscopic investigation by neutron scattering shows than in the VFT regime of the fast process the dynamics present a diffusive nature similar to bulk water. A large distribution of diffusion coefficients indicates possible differences in the connectivity of the hydrogen bond network. Diffusive heterogeneous dynamics can arise from a nonuniform distribution of water. The confinement effect of the polymer matrix is detected as a considerable reduction of the diffusion coefficient of water with respect to bulk. The presence of a crystalline phase results in a slowing down of both the fast and slow processes involving water motions. This could give a hint to the presence of a rigid amorphous phase in the semicrystalline material.
Authors with CRIS profile
Involved external institutions
University of Basque Country / Universidad del Pais Vasco (UPV) / Euskal Herriko Unibersitatea (EHU)
Spain (ES)
Spanish National Research Council / Consejo Superior de Investigaciones Científicas (CSIC)
Spain (ES)
Paul Scherrer Institute (PSI)
Switzerland (CH)
Forschungszentrum Jülich / Research Centre Jülich (FZJ)
Germany (DE)
Spain (ES)
Spanish National Research Council / Consejo Superior de Investigaciones Científicas (CSIC)
Spain (ES)
Paul Scherrer Institute (PSI)
Switzerland (CH)
Forschungszentrum Jülich / Research Centre Jülich (FZJ)
Germany (DE)
How to cite
APA:
Laurati, M., Sotta, P., Long, D.R., Fillot, L.A., Arbe, A., Alegria, A.,... Colmenero, J. (2012). Dynamics of Water Absorbed in Polyamides. Macromolecules, 45(3), 1676-1687. https://dx.doi.org/10.1021/ma202368x
MLA:
Laurati, M., et al. "Dynamics of Water Absorbed in Polyamides." Macromolecules 45.3 (2012): 1676-1687.
BibTeX: Download