title: Intelligent reversible nanoporous antireflection film by solvent-stimuli-responsive phase transformation of amphiphilic block copolymer.
abstract: An erasure-reconstruction porous structure with reversible antireflection (AR) property at near-infrared region (NIR) was prepared for the first time based on solvent-stimuli-responsive phase transformation of polystyrene-block-poly(4-vinypyridine) (PS-b-P4VP). The inhomogeneous porous structure with a dense skin and porous underneath, which was obtained by the nonsolvent-induced phase separation of PS-b-P4VP film from micelle solution with mixed solvents (tetrahydrofuran and dimethylformamide), was used as starting porous film. Then, the film was annealed by PS-selective solvent to erase the nanopores because the PS block was swollen effectively by its selective solvent. Afterward, the nonporous film was immersed in linear aliphatic acid to reconstruct the nanoporous structure (loosely packed micelles) by the combination of the hydrogen bond interaction and the positively charge-induced repulsion between each chain. Thus, an intelligent reversible AR property in the NIR region between a high-transmittance porous state (∼99.0%) and a low-transmittance nonporous state (∼90.0%) was realized by alternate treatments of PS-selective solvent and linear aliphatic acids. This reversible erasure-reconstruction porous structure for switching between AR (98.0%) and non-AR (90.0%) properties could be recycled by at least four times.
authors: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, People's Republic of China.
authors: Xiao
authors: X
authors: Li
authors: Xinhong
authors: X
authors: Yu
authors: Yanchun
authors: Y
authors: Han
mesh_terms: D049329:Nanostructures / Q000737:chemistry*; D010316:Particle Size; D011137:Polystyrenes / Q000138:chemical synthesis / Q000737:chemistry*; D011145:Polyvinyls / Q000138:chemical synthesis / Q000737:chemistry*; D016062:Porosity; D012997:Solvents / Q000737:chemistry; D013499:Surface Properties; D013501:Surface-Active Agents / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D011137:Polystyrenes; D011145:Polyvinyls; D012997:Solvents; D013501:Surface-Active Agents; C521882:poly(styrene)-block-poly(4-vinylpyrindine) diblock copolymer