Chitosan-based hydrogels obtained via photoinitiated click polymer IPN reaction

Chitosan (CTS) is a polysaccharide with a wide variety of applications in the biomedical field, owing to its outstanding disinfectant properties, biocompatibility and biodegradability, but with limited mechanical properties. The proposed strategy to improve CTS-based hydrogel properties in this study is the forma-tion of a semi-interpenetrating polymer network (semi-IPN). In this way, a photo-initiated radical click reaction was proposed to obtain a synthetic polymer, whose components were included in a CTS solution, resulting in the semi-IPN network after UV illumination. Different crosslinking degrees (CD) and CTS/ polymer ratios were evaluated through rheological characterization, along with an assessment of both variables based on an experimental model design, obtaining that, for every CTS/polymer ratio, interme-diate values of CD (8 %) offered the best rheological properties. In addition, chemical and microstructural characterization were carried out for selected hydrogels, obtaining consistent results according to rheo-logical characterization, as the 1/1 CTS/polymer ratio with CD 8 % hydrogel displayed the most homoge-neous pore size and distribution, consequently leading to the best rheological performance.(c) 2023 The Author(s). Published by Elsevier B.V.