Fig. 4.
Spontaneous forgetting process of PA gels. (A) Example to show spontaneous forgetting process of a gel experienced an 80 °C–5 min–25 °C learning process to memorize an airplane pattern. The elapsed time after cooling in 25 °C bath is shown in the photos. (B and C) Effect of thermal learning time tL on memory strength (B) and forgetting time tF (C) for the same TL and TF. The time in the images is the learning time tL. (D and E) Effect of thermal learning temperature TL on memory strength (D) and forgetting time tF (E) for the same tL and TF. The temperature in the images is the learning temperature TL. In all experiments, tL is shorter than the equilibrium swelling time of sample and the forgetting time tF is determined by the recovery time from opaque to transparent. (Scale bars, 1 cm.)