Journal of Materials Science

, Volume 32, Issue 21, pp 5825–5832 | Cite as

Manufacture of biodegradable packaging foams from agar by freeze-drying



Cellular foams were made from the aqueous solution of agar by freeze-drying. A narrow range (5–20°C min-1) of freezing rate was required to avoid damage to the microstructure of the agar foams. The size of cells in the foam decreased with increasing freezing rate. Agar foams of more than 4 wt% agar content absorbed more energy than a polystyrene foam in compression tests. Foams with a higher agar content absorbed more energy. The behaviour of agar foams in compression tests could be explained by the modified beam theory for cellular foams. Agar foams were thermally stable up to 200°C, and were also stable in a humid environment.


Foam Agar Content Freezing Rate Plateau Stress Polystyrene Foam 


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Copyright information

© Chapman and Hall 1997

Authors and Affiliations

    • 1
    • 1
    • 1
  1. 1.Department of Chemical EngineeringPohang University of Science and TechnologyNam-Ku, Pohang KyungbukSouth Korea

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