Mechanical, rheological, nanoindentation and degradability evaluation of soft composite Chitosan/Pectin/NaCl hydrogels with cellulose nanowhiskers

Abstract

Chitosan and pectin form biocompatible polyelectrolyte complex hydrogels. This study investigates the impact of cellulose nanowhiskers (CNW) and NaCl on hydrogel’s properties, particularly in mechanical behavior. Swelling tests revealed deswell-ing under physiological conditions. Thermal analysis indicated enhanced crosslinking with CNW, correlating with mechani-cal, rheological, and nanoindentation findings. Hydrogels with 10% CNW exhibited higher elastic modulus in compression tests. Rheological studies showed comparable values to skin, promising for wound dressing applications. Nanoindentation highlighted CNWs' surface effect on adhesive modulus. Degradation tests over 21days demonstrated higher degradation in NaCl-containing hydrogels. Overall, NaCl influenced polymer matrix interactions, while CNW incorporation enhanced hydrogel performance. This study distinguishes between surface and bulk properties of hydrogels, underscoring the potential of CNW in biomaterial applications.