Abstract:The GG/PAAm double network hydrogel was prepared by a simple“one pot method”of aqueous mixture of gellan gum (GG), acrylamide (AAm), containing N,N""-methylenebisacrylamide(MBA) as crosslinking agent，the Ag+ enhanced GG/PAAm double network hydrogel was obtained after soaking in silver nitrate solution. The effects of AAm、MBA content and Ag+ on the hydrogel rheological properties, microstructure and mechanical properties were studied, the results showed that a series of hydrogels could be prepared by changing the amount of crosslinking agent MBA in the system, SEM showed the double network hydrogel has an interconnected porous structure, the storage modulus of GG/PAAm hydrogels increased and tan δ decreased significantly with the increase of MBA content in the hydrogel, due to the fact that an increasingly perfect network structure is formed inside the GG/PAAm hydrogel, indicating that the elastic properties are dominant in the hydrogel. After immersed in silver nitrate solution, Ag+ can reorganizes the network structure, both the storage modulus and mechanical performance of GG/PAAm hydrogel is obviously enhanced, the storage modulus (G"") of hydrogel rapidly increases from 7.5 kPa to 38 kPa, which is more than 5 times higher than that of the GG/PAAm hydrogel, the compressive strength can reach 11.8 MPa, much higher than GG/PAAm hydrogel (compression strength is 4.88 MPa), and elongation at break increased from 236 % to 320 %, and fracture strength increased from 0.1 MPa to 0.26 MPa. Meanwhile, antibacterial experiments show that Ag+ enhanced GG/PAAm double network hydrogel has good antibacterial properties. Considering these excellent performance, this composite hydrogels have great potential application in antibacterial materials.