Figure 5: For F5P3, the is about one order of magnitude larger than the initially after mixing of silk fibroin and PNIPAAm aqueous solutions. As the system ages, the increases rapidly and crosses over about 8 min after mixing with a sweep frequency of 0.5 Hz, while the crossing of over occurred about 80 min later when the sweep frequency was set to 1.5 Hz. The complex modulus G* shows slight difference at varied sweep frequency.