Mechanically strong hybrid double network hydrogels with antifouling properties

The development of mechanically tough and biocompatible polymer hydrogels has great potential and promise for many applications. Herein, we synthesized a new type of hybrid physically-chemically crosslinked Agar/PAM double network (DN) hydrogel using a simple, one-pot method. Agar/PAM gels are designed with desirable/balanced mechanical properties by varying the network-forming parameters. Among them, a strong Agar/PAM DN gel achieves the highest tensile stress of 3.3 MPa at failure strain of 2400%, while a tough DN gel achieves the tensile strain of 3700% at failure stress of 2.8 MPa. Besides excellent mechanical properties, Agar/PAM DN hydrogels exhibited excellent antifouling properties to highly resist protein adsorption, cell adhesion, and bacterial attachment, as well as the free shapeable property to form any complex shapes. The relationship between mechanical properties and antifouling performance was discussed. We hope that the combination of the mechanical and antifouling properties in Agar/PAM gels will make them as promising "biomimetic'' materials for many bio-inert applications.