Nanoporous Films with Sub‐10 nm in Pore Size from Acid‐Cleavable Block Copolymers. Issue 5 (24th January 2017)

• Record Type: Journal Article
• Authors: Li, Yayuan; Xu, Yawei; Cao, Shubo; Zhao, Yongbin; Qu, Ting; Iyoda, Tomokazu; Chen, Aihua
• Is Part Of: Macromolecular rapid communications. Volume 38:Issue 5(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-01-24
• Subjects: block copolymer -- nanoporous film -- self‐assembly -- sub‐10 nm; Macromolecules -- Periodicals; Polymers -- Periodicals; Chemistry -- Periodicals; 547.705
• DOI: 10.1002/marc.201600662
• Languages: English
• ISSNs: 1022-1336

Abstract

Abstract : Ordered nanoporous thin films with pore size sub‐10 nm are formed by using a degradable block copolymer, an acid‐cleavable benzoic imine juncture introduced between poly(ethylene oxide) (PEO) and poly(methacrylate) (PMAAz) bearing an azobenzene segment in the side chain, denoted as PEO‐ bei ‐PMAAz, as a precursor. The pore density of the final PMAAz nanoporous films can reach to 10 12 cm −2 . Abstract : Nanoporous thin films with pore size of sub‐10 nm are fabricated using an acid‐cleavable block copolymer (BCP), a benzoic imine junction between poly(ethylene oxide) (PEO) and poly(methacrylate) (PMAAz) bearing an azobenzene side chain (denoted as PEO‐ bei ‐PMAAz) as the precursor. After a thermal annealing, the block copolymers are self‐assembled to form highly ordered PEO cylinders within a PMAAz matrix normal to the film, even in the case of low BCP molecular weight due to the existing of the liquid crystalline (LC) azobenzene rigid segment. Thus, PMAAz thin films with pore size of ≈7 nm and density of ≈10 12 cm −2 are obtained after removal of the PEO minor phase by breaking the benzoic imine junction under mild acidic conditions. This work enriches the nanoporous polymer films from BCP precursors and introduces the LC property as a functionality which can further enhance the mechanical properties of the films and broaden their applications.