The incorporation of OTPh or P3HT into NaDC hydrogels does not alter the mechanical properties of the NaDC gel. The viscoelastic properties of the gels were studied by rheology (Figure ). For a gel, the storage modulus (G') is higher than the loss modulus (G") indicating that the elastic behavior is dominant. In the linear viscoelastic region, the strain is not sufficient to break the molecular interactions that form the gel. Above the critical strain, the gel breaks down which led to the decrease of both G' and G", and G" became higher than G' indicating that the viscous behavior became dominant. The linear viscoelastic region was determined in amplitude sweep experiments and the critical strain for NaDC, OTPh/NaDC and P3HT/NaDC is ca. 1%