AI Article Synopsis
- The viscoelastic properties of alginate biopolymer are crucial for its effectiveness in biomedical applications, mimicking biological matrix properties.
- Stress relaxation of glycerol plasticized sodium alginate films is tested at two humidity levels, showing that glycerol concentration significantly influences relaxation behavior.
- Specifically, films with 30% glycerol exhibit a drop in normalized stress from 65% at low humidity to 8% at high humidity, while glycerol-free films show higher stresses, indicating the need for careful modeling of relaxation time, especially for lower glycerol concentrations.
Article Abstract
The control of viscoelastic properties of alginate biopolymer that mimics the matrix properties of biological substrates plays an important role for the success of its biomedical applications. For this purpose stress relaxation behavior of glycerol plasticized sodium alginate films is characterized at room temperature as a function of the glycerol concentration ranging up to 40%. A series of experiments are thus conducted at relative humidity levels of 38 ± 1% and 51 ± 1%. The glycerol content is demonstrated to amplify the effect of humidity on relaxation profiles. In the case of 30% glycerol, normalized stress at the level of 65% is recorded at the end of the first 30 min at the low humidity level, whereas the corresponding value drops to 8% with increased humidity. Alginate films with no glycerol content exhibit much higher normalized stresses of 89% and 73% at low and high humidity levels, respectively. In addition, stress relaxation is observed to continue well beyond the first 30 min, especially for glycerol concentrations lower than 30%, where 9-hour parameters for a stretched exponential Kohlrausch - Williams - Watts function are reported demonstrating the importance of relaxation time for successful modeling.
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| http://dx.doi.org/10.1016/j.jmbbm.2019.103374 | DOI Listing |
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