Tailored covalently cross-linked hydrogels based on oxidized cellulose sulfate and carboxymethyl chitosan by targeted adjustment of the storage modulus

Abstract

In general hydrogel synthesis uses a trial and error method when creating new hydrogels and searches afterwards for a fitting application of the received hydrogel. A much more effective and sustainable approach would be to have an application in mind before starting a targeted synthesis of a hydrogel with specific properties. Hence the goal of the study is to investigate influencing factors—crosslink density here represented through the degree of substitution, mass average molecular mass, mixing ratio and time for gelation—to the storage modulus G′ for covalently cross-linked hydrogels based on oxidized cellulose sulfate and carboxymethyl chitosan. The results can be summarized as follows: higher values for G′ can be reached by increasing the mass average molecular mass, the crosslink density and by shifting the mixing ratio toward the polymer which determines the number of possible cross-linkings in the hydrogel. The findings of this work may be transferred to similar systems and are helpful for a targeted synthesis of hydrogels with specific characteristics.