Donor–acceptor covalent organic frameworks for visible light induced free radical polymerization. Issue 36 (16th August 2019)

• Record Type: Journal Article
• Authors: Pachfule, Pradip; Acharjya, Amitava; Roeser, Jérôme; Sivasankaran, Ramesh P.; Ye, Meng-Yang; Brückner, Angelika; Schmidt, Johannes; Thomas, Arne
• Is Part Of: Chemical science. Volume 10:Issue 36(2019)
• Page Start: 8316
• Page End: 8322
• Publication Date: 2019-08-16
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c9sc02601k
• Languages: English
• ISSNs: 2041-6520

Abstract

Abstract : Crystalline and porous covalent organic frameworks (COFs) with donor-acceptor moieties in their backbone are utilized as initiators for visible light induced radical polymerization. The COFs are efficient photoinitiators, maintaining their structural integrity for several cycles. Abstract : Covalent organic frameworks (COFs) are promising materials for applications in photocatalysis, due to their conjugated, porous and chemically stable architectures. Alternating electron donor–acceptor-type structures are known to enhance charge carrier transport mobility and stability in polymers and are therefore also interesting building units for COFs used as photocatalysts but also as photoinitiator. In this work, two donor–acceptor COFs using electron deficient 4, 4′, 4′′-(1, 3, 5-triazine-2, 4, 6-triyl)trianiline and electron rich thiophene-based thieno[3, 2- b ]thiophene-2, 5-dicarbaldehyde or [2, 2′-bithiophene]-5, 5′-dicarbaldehyde linkers are presented. The resulting crystalline and porous COFs have been applied as photoinitiator for visible light induced free radical polymerization of methyl methacrylate (MMA) to poly-methyl methacrylate (PMMA). These results pave the way to the development of robust and heterogeneous systems for photochemistry that offers the transfer of radicals induced by visible light.