Ice-templated hydrogels based on chitosan with tailored porous morphology

Preparation and morphological characterization of some novel hydrogels based on chitosan (CS) with porous structure tailored by ice-templating and porogen leaching are presented in the paper. Poly(methylmethacrylate) (PMMA), as fractionated particles, has been used as polymer porogen. The influence of the mesh of the fractionated PMMA particles, the weight ratio between CS and fractionated PMMA particles, and the speed of the crystallization, on the internal morphology of the hydrogels have been deeply investigated. The morphology of the obtained hydrogels was observed by scanning electron microscopy (SEM). As a function of the synthesis conditions, hydrogels with a heterogeneous morphology consisting of randomly and evenly distributed polyhedral pores, or with an oriented structure, which has microchanneled structures arranged along the freezing direction, were generated.