Synthesis of a Nanoporous Polymer with Hexagonal Channels from Supramolecular Discotic Liquid Crystals

Abstract

Des Polymers Kern (wird zum Schluss entfernt): Wasserstoffbrücken‐Wechselwirkungen zwischen einem Benzotri(imidazol)‐Derivat und einer polymerisierbaren Alkoxybenzoesäure führen zur Bildung supramolekularer hexagonaler columnarer Flüssigkristalle. Durch lichtinduzierte Polymerisation und anschließendes Entfernen des Benzotri(imidazol)‐Kerns entsteht hieraus ein poröses Polymer mit hexagonalen Kanälen (siehe schematische Darstellung).

Functional Organic Materials Based on Polymerized Liquid‐Crystal Monomers: Supramolecular Hydrogen‐Bonded Systems

“…Kim and co‐workers have prepared a hexagonal columnar polymer film consisting of a benzotri(imidazole) 17 core and photopolymerizable trialkoxybenzoic acid acrylate 16 that form a 1:3 supramolecular complex through hydrogen‐bonding (Figure 7 a). 31 After photopolymerization, the hexagonal columnar LC phase was fixed in a cross‐linked polymer film. Interestingly, treatment of the polymer film with acidified methanol resulted in removal of the benzotri(imidazole) core and produced a nanoporous hexagonal film (Figure 7 b).…”

“…c) Schematic representation of desorption and adsorption of 18 in the nanoporous columnar liquid‐crystalline polymer film based on 16 . Reproduced with permission from references 31 and 36. Copyright Wiley‐VCH.…”

Ordered Mesoporous Polymers and Homologous Carbon Frameworks: Amphiphilic Surfactant Templating and Direct Transformation

“…However, most of the resulting porous polymer structures are disordered with wide pore size distributions because of the contraction and swelling from changes in volume, as well as the structured defects formed during template removal 10. Large porosities have rarely been reported 11. Furthermore, the resistance of the pore structure to heat and solvents is rather low because the materials are formed by weak van der Waals forces and physical twists between polymer chains, which means that the framework is not connected by covalent bonds.…”

Fabrication of conjugated polymeric nanochannels from star-shaped supramolecular liquid crystals containing two different photoreactive groups

“…Lyotropic liquid crystals are often used for preparation of nanoporous polymers, [31][32][33] but thermotropic liquid crystals have also been utilised. [34,35] We previously found that star-shaped supramolecular liquid crystals formed by simple hydrogen bonding exhibit a variety of discotic mesophases, and the single hydrogen bonding between phenol and pyridine moieties can be a simple and effective method for constructing elaborate columnar structures. [36][37][38] Recently, we reported a new route to fabricate conjugated polymeric columns with a twodimensional hexagonal symmetry using star-shaped supramolecular liquid crystals as photoreactive monomers.…”