Porphyrinic Zirconium Metal-Organic Frameworks (MOFs) as Heterogeneous Photocatalysts for PET-RAFT Polymerization and Stereolithography

Liwen Zhang; Xiaobing Shi; Zhiheng Zhang; Rhiannon P Kuchel; Rashin Namivandi-Zangeneh; Nathaniel Corrigan; Kenward Jung; Kang Liang; Cyrille Boyer

doi:10.1002/anie.202014208

Porphyrinic Zirconium Metal-Organic Frameworks (MOFs) as Heterogeneous Photocatalysts for PET-RAFT Polymerization and Stereolithography

Angew Chem Int Ed Engl. 2021 Mar 1;60(10):5489-5496. doi: 10.1002/anie.202014208. Epub 2021 Jan 15.

Authors

Liwen Zhang¹, Xiaobing Shi¹, Zhiheng Zhang¹, Rhiannon P Kuchel², Rashin Namivandi-Zangeneh¹, Nathaniel Corrigan¹, Kenward Jung¹, Kang Liang^{1

3}, Cyrille Boyer¹

Affiliations

¹ Australian Centre for NanoMedicine, Centre for Advanced Macromolecular Design, School of Chemical Engineering, The University of New South Wales, Sydney, New South, Wales, 2052, Australia.
² Electron Microscope Unit, Mark Wainwright Analytical Centre, The University of New South Wales, Sydney, New South Wales, 2052, Australia.
³ Graduate School of Biomedical Engineering, The University of New South Wales, Sydney, New South Wales, 2052, Australia.

PMID: 33179352
DOI: 10.1002/anie.202014208

Abstract

In this study, porphyrinic zirconium (Zr) MOFs were investigated as heterogeneous photocatalysts for photoinduced electron transfer-reversible addition-fragmentation chain transfer (PET-RAFT) polymerization of various monomers under a broad range of wavelengths, producing polymers with high monomer conversions, narrow molecular weight distributions, low dispersity and good chain-end fidelity. Screening of various porphyrinic Zr-MOFs (Zn) containing Zn-metalled porphyrinic ligands demonstrated that MOF-525 (Zn) with the smallest size had the best photocatalytic activity in PET-RAFT polymerization, due to enhanced dispersion and light penetration. Oxygen tolerance and temporal control were also demonstrated during MOF catalysed PET-RAFT. Results suggested that the polymerization rates were significantly affected by changing the size and surface area of MOFs, and the heterogeneous MOF photocatalysts could be easily separated and recycled for up to five independent PET-RAFT polymerizations without an obvious decrease in efficiency. Finally, the MOF photocatalysts were utilized to create three-dimensional polymeric objects with high resolution via visible light mediated stereolithography in an open-air environment.

Keywords: 3D printing; green chemistry; metal-organic frameworks (MOFs); photopolymerization; stereolithography.