Abstract
The relation between the self-diffusion coefficient, D-self, of water and the free volume hole size, V-h, has been investigated in a hydroxypropyl methylcellulose (HPMC)-water system in the water content range 0.08-0.36 w/w, at room temperature. Furthermore, the thermal properties of the water in the HPMC-water system, as measured with differential scanning calorimetry (DSC) and the tensile storage, E', and tensile loss, E '', moduli, of the HPMC-water systems, as determined with dynamic mechanical analysis (DMA), have been probed. Pulsed-field gradient nuclear magnetic resonance (PFG NMR) was used to measure the D-self of water and positron annihilation lifetime spectroscopy (PALS) was used to measure the ortho-Positronium (o-Ps) lifetime in the HPMC-water system. The glass transition temperature of the HPMC was found to be reduced by the water to room temperature in the water content range 0.10-0.15 w/w. The relation between ln D-self of water and the inverse free volume hole size of the HPMC-water system was non-linear. Furthermore, the PALS measurements showed that molecular water co-existed with water clusters in the HPMC-water system. (C) 2009 Elsevier Ltd. All rights reserved.
Original language | English |
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Pages (from-to) | 2812-2820 |
Journal | European Polymer Journal |
Volume | 45 |
Issue number | 10 |
DOIs | |
Publication status | Published - 2009 |
Bibliographical note
The information about affiliations in this record was updated in December 2015.The record was previously connected to the following departments: Polymer and Materials Chemistry (LTH) (011001041)
Subject classification (UKÄ)
- Chemical Sciences
Free keywords
- Water clusters
- Self-diffusion coefficient
- Free volume
- Positron
- annihilation
- NMR