FE-SEM observation, and mechanism of interaction of wet agar gel in various swelling conditions using hydrophilic ionic liquid

Wet agar gels of various swelling conditions were prepared by mixing agar, water and heating for different time, and, subsequently treated with ionic liquid (IL) in such a way that water content of the agar gels were fixed to 30 mol%. FE-SEM photographs showed that the exact morphology of these wet agar gels could be successfully observed within 1% in difference up to 1 h under high vacuum. In order to explain the mechanism of FE-SEM observation of wet agar gel using IL, the existence of IL within agar gel after displaced water derived from agar gel was investigated by DSC. From DSC results it was noticed that binding ability of IL and water within agar gel prevents the gel from drying and retain the morphology. Additionally, it was noticed that transition of individual water molecules to large water clusters increased above 30 mol% water concentration of IL and water mixture. Dimensional measurement showed that these wet agar gels showed less than 1% in linear shrinkage. Thus IL treated wet agar gels of different swelling conditions could be observed by FE-SEM and the mechanism was explained in terms of DSC results.