1. Structure-property interpretation of biological polyhydroxyalkanoates with different monomeric composition: Dielectric spectroscopy investigation.
- Author
-
Ishak KA, Velayutham TS, Annuar MSM, and Sirajudeen AAO
- Subjects
- Calorimetry, Differential Scanning, Glass chemistry, Macromolecular Substances, Molecular Structure, Structure-Activity Relationship, Temperature, Transition Temperature, Dielectric Spectroscopy methods, Polyhydroxyalkanoates chemistry, Polyhydroxyalkanoates metabolism
- Abstract
Dielectric spectroscopy is employed to study the relaxation phenomena in natural polyhydroxyalkanoates (PHAs) upon temperature and frequency variations. Effects of PHAs molecular structure on the relaxation, arising from the differences in monomeric composition, are investigated under identical conditions in a frequency range of 10
-2 -106 Hz, and at different temperatures. All PHA samples showed different dielectric response at different temperature. Primary α-relaxation signals are observed at temperature corresponding to the glass transition temperature. On the other hand, secondary β- and γ-relaxations are detected at low temperatures, and attributed to local motions of polar groups and small segments of the polymer chain. The dielectric properties of representative PHA samples are compared and discussed., Competing Interests: Declaration of competing interest All authors declare no conflict of interest financially or otherwise., (Copyright © 2020 Elsevier B.V. All rights reserved.)- Published
- 2021
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