In situ polymerization approach to cellulose–polyacrylamide interpenetrating network hydrogel with high strength and pH-responsive properties

Cellulose hydrogels usually have poor mechanical properties which seriously limit their applications in biomedical or industrial fields. Herein, an interpenetrating polymer network strategy was proposed to construct double network hydrogels composed of cellulose and polyacrylamide with high mechanical strength and pH responsive properties. The synergistic interactions and strong hydrogen bonds between two networks contributed to the dissipation of mechanical energy, as evidenced by the compressive stress–strain and rheology analyses. The compressive strength and compressive modulus for cellulose–polyacrylamide interpenetrating network (C–PAM IPN) hydrogels could reach up to 5.62 and 22.47 MPa, which is nearly 18 and 23 times higher than that of cellulose hydrogels. Moreover, these tough C–PAM IPN hydrogels exhibit pH sensitive properties in various pH solutions. Therefore, this paper provides a general strategy to enhance the mechanical and physical properties of cellulose-based hydrogels, which are potentially useful in developing novel cellulose-based hydrogels and expanding their applications.