Fig. 2
NanoPE fabrication and characterization. a Schematic of hot-press to fabricate nanoPE. b–d Pore-size distribution of nanoPE films with mixing ratios of 1:3, 1:5, and 1:7 (inset shows the corresponding SEM images and photos of samples). e–g Visible light reflection of nanoPE films with different thicknesses and mixing ratios. h–j MIR transmittance of nanoPE films with different thicknesses and mixing ratios. k Scattering efficiency of nano-sized pores in the visible band by Mie scattering theory. l Scattering efficiency of nano-sized pores in the mid-infrared band by Rayleigh scattering theory. m Biaxial orientation stretching machine with PE film. n The BOPE film in dry process. o The visible reflectance of BOPE film with different thicknesses. p The mid-infrared transmittance of BOPE film with different thicknesses. q SEM of BOPE in the wet process as well as the scalable nanoPE. r The visible reflectance of scalable nanoPE with different thicknesses. s The mid-infrared transmittance of scalable nanoPE with different thicknesses. t Tensile stress of nanoPE films with different thicknesses
