Figure 2.

(A) Chemical structure of the PABBP copolymer. (B) Schematic representation of the bilayer structure of the PFM. (C) Photographs of the light-controlled motion of an isopropanol slug climbing over a slope of 11° incline in a curved PFM. The intensity of the 470 nm point light was 120 mW cm⁻². The scale bar is 2 mm. (A–C) Reprinted with permission from Xu et al. (2019) Copyright Wiley-VCH. (D) The chemical structure and photoisomerization of P1. (E) Schematic representation of entanglement of polymer chains. The freestanding film of entangled P1 was highly transparent (F), flexible (G), and stretchable at 90°C (H). (D–H) Reprinted with permission from Chen et al. (2020) Copyright Wiley-VCH.