Fracture resistance of polyacrylamide-alginate hydrogels

•Similar fracture behaviour through rubbers method and nonlinear fracture mechanics.•A tearing modulus parameter dependent on the strain energy density is proposed.•Crack blunting holds constant during crack propagation.•Steady regime during crack propagation.•Strain field at crack front maintains constant during crack propagation.•Alginate content increase fracture resistance and crack stability.