Abstract
Water in polymer gels remains sometimes unfrozen during cooling to turn into a glassy state, and to crystallise during subsequent warming. As change in the polymer network on freezing is seen to be a primary cause for the occurrence of a glass transition, and both freezing and drying are dehydration processes from around polymers, observation of structural change of crosslinked dextran gel beads was conducted during absorption/desorption or freezing by using an environmental SEM to investigate their dependency on the crosslink density. It was confirmed by the observation that the polymer gel beads with lower crosslink density are ready to change their bead structure during drying and freezing, and that they are more flexible than those with higher crosslink density.
