Extended Data Fig. 2: Fabrication of WRAP films.

a, Schematic and photographs of stepwise fabrication process of free-standing IC/PEO thin film. b, All-atom MD simulations of spontaneous formation of inclusion complex in solution. As PEG (n = 9) polymer penetrate through the α-CD, their interaction energy decreases. After formation of inclusion complex, the structure remains stable in long time simulation. c, MD simulations of crystalline inclusion complex which is stable and maintains the structure after 100 ns simulation in solution. d, Tensile stress-strain curves for films drawn at 2 mm s⁻¹ show IC/PEO is stiffer (E about 545 MPa) but less stretchable (around 400%) than a pure PEO thin film (370 MPa,  650%). e-f, Relationship between elongation ratio and cycle numbers for different preset stresses (15 MPa to 30 MPa) and crosshead speeds (0.5 mm s⁻¹ to 4 mm s⁻¹) show elongation ratio increased linearly with cycle numbers for all conditions(e). Time-dependent change in elongation ratio under crosshead speeds of 0.5 mm s⁻¹, 2 mm s⁻¹ and 4 mm s⁻¹ shows drawing at 2 mm s⁻¹ is most efficient (f). The higher preset stress and lower drawing speed result in larger elongation ratios’ increase for each cycle. However, the film broke during cold-drawing at a preset stress of 30 MPa and lower drawing speed also means more time is required to reach a certain elongation. Therefore, optimal preset stress and drawing speed for are 25 MPa and 2 mm s⁻¹ respectively. g, Photographs of IC/PEO (elongation 0%) and WRAP films with elongation ratios ranging from 218% to 700% (WRAP-218% to WRAP-700%). Scale bar: 1 cm.