High-toughness polyacrylamide gel containing hydrophobic crosslinking and its double network gel

Tough polyacrylamide gel containing hydrophobic crosslinking (HPAAm gel) was easily synthesized by γ-radiation induced micelle copolymerization and crosslinking of a hydrophobic monomer, stearyl acrylate (STA), and acrylamide. HPAAm gel could still keep intact after compressed to the strain of 0.9 while the corresponding polyacrylamide gel prepared by adding chemical crosslinker has been broken. Meanwhile, elongation at break of HPAAm gel could reach 1000%, which is also much higher than conventional polyacrylamide gels, indicating the high toughness of HPAAm gel. Furthermore, double network polyacrylamide hydrogel containing hydrophobic crosslinking (DN-HPAAm) was synthesized by incorporating another PAAm network into the prepared HPAAm gel. The resultant DN-HPAAm gel has much better compression strength (∼2 MPa) than HPAAm gel and a good cycle compression property.