Multifunctional Poly(acrylic acid)/Chitosan nanoparticle network hydrogels with tunable mechanics

Abstract

Nanoparticle network hydrogels (NNHs) employ nanoparticles as key building blocks of hydrogel networks to provide excellent mechanical properties and multifunctionality. Herein, poly(acrylic acid)/chitosan nanoparticle network hydrogels (PAAc/CS NNHs) with prominent mechanical properties were fabricated using catechol functional methacryloyl chitosan-silver nanoparticles (CFMC-Ag NPs) as multifunctional nanoparticle crosslinkers. The PAAc/CS NNHs were composed of hybrid networks derived from CFMC-Ag NPs crosslinked PAAc and entangled chitosan (CS) chains. The mechanical properties of PAAc/CS NNHs were highly impacted by the concentration of CFMC-Ag NPs. A maximum tensile strength of 2.22 MPa, a compressive strength of 10.61 MPa, and a toughness of 5.57 MJ·m−3 were obtained at a nanoparticle concentration of 10 mg/mL. In addition, PAAc/CS NNHs exhibited great self-recovery performance and excellent fatigue resistance. It was demonstrated that PAAc/CS NNHs possessed antibacterial activity, electrical conductivity and anti-freezing capability. This strategy could be applied for the preparation of other multifunctional hydrogels with significant mechanical properties.