Fig. 2.

Rheological measurements of composite hydrogel and hydrogel–GNR. a Temperature-dependent transmittance of hydrogel and hydrogel–GNR, and the temperature corresponding to the abrupt drop point is designated as the LCST. b Compressive stress–strain curves of hydrogel, hydrogel–GNR (20 ppm), and hydrogel–GNR (50 ppm), respectively. c Strain amplitude sweeps of hydrogel and hydrogel–GNR performed at 39 °C at a constant frequency of 1 rad s⁻¹, d Dynamic oscillatory frequency sweeps of hydrogel and hydrogel–GNR at a fixed strain of 1%. e, f Time-dependent sweep tests of hydrogel (e) and hydrogel–GNR (f). Notes: hydrogel represents CS/mPEG-Mal/pNIPAAm-co-AAc with 20% AAc in pNIPAAm-co-AAc.