Supercritical−CO₂ Dried Biodegradable Alginate/Zirconia Aerogels: Synthesis and Characterization
Nur Hazwani Dalili MOHAMAD, Ana Najwa MUSTAPA, Suhaiza Hanim HANIPAH
Abstract. This work presents the synthesis of new biodegradable alginate-zirconia (AG-ZR) hybrid aerogels as a potential thermal insulator material. The effect of the alginate-to-zirconia ratio on their physical and chemical characteristics is investigated. Hybrid gels containing 3–5 wt% alginate and 0.05–0.2 wt% zirconia were prepared via solvent casting, followed by supercritical carbon dioxide (Sc-CO₂) drying to obtain lightweight aerogels. The physical and chemical properties were characterized by Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) analysis. Results showed that the chemical interaction between alginate and zirconia was identified by the characteristic Zr−O and −COO− stretching vibrations. Thermogravimetric analysis (TGA) indicated considerable thermal stability up to 350°C, while differential scanning calorimetry (DSC) suggested that degradation commenced at approximately 270°C. Mechanical testing revealed that the aerogel formulation composed of 5 wt.% alginate and 0.2 wt.% zirconia exhibited a notable tensile strength of approximately 1.8 MPa and improved flexibility, as indicated by elongation at break. The synthesized AG-ZR hybrid aerogels showed strong chemical crosslinking, excellent thermal stability, and superior mechanical strength, particularly in AG 5:ZR 0.2 formulation. The findings demonstrate the potential of the material as a lightweight, biodegradable, and thermally stable insulation solution for advanced engineering applications.
Keywords
Aerogel, Alginate, Zirconia, Supercritical Drying, Thermal Insulation
Published online 1/15/2026, 8 pages
Copyright © 2026 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Nur Hazwani Dalili MOHAMAD, Ana Najwa MUSTAPA, Suhaiza Hanim HANIPAH, Supercritical−CO₂ Dried Biodegradable Alginate/Zirconia Aerogels: Synthesis and Characterization, Materials Research Proceedings, Vol. 59, pp 113-120, 2026
DOI: https://doi.org/10.21741/9781644903957-15
The article was published as article 15 of the book Separation Technology
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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