Advancing photopolymerization and 3D printing: High-Performance Ni II complexes bearing N 2 O 2 Schiff-base ligands as photocatalysts

Autor(es)

Pesqueira, Naralyne M. ; Morlet-Savary, Fabrice ; Schmitt, Michael ; Carvalho-Jr, Valdemiro P. ; Goi, Beatriz E. ; Lalevee, Jacques

• Tipo de documento: Artigo Científico
• Fonte: EUROPEAN POLYMER JOURNAL; v. 216, p. 13-pg., 2024-07-03.

Resumo

New high-performance photocatalysts based on metal structures are being developed for polymerization. However, using low-cost metals while ensuring effectiveness is challenging. In this study, two Ni II complexes NiL1 and NiL2 were synthesized using N 2 O 2 Schiff-base ligands bearing pi-extended rings (naphthaldehyde ( H 2 L1 ) and phenylsalicylaldehyde ( H 2 L2 ) groups), respectively. These complexes were characterized by FTIR, UV-Vis and 1 H NMR spectroscopy, elemental analysis, cyclic voltammetry, and MALDI-TOF mass spectrometry. NiL1 and NiL2 were evaluated in photoinitiating system as new photocatalysts for the Free Radical Photopolymerization of Ethoxylated (3) Trimethylolpropane Triacrylate (TMPETA) for violet and green light. Threecomponent systems were employed in the presence of Di- tert-butyl-diphenyl iodonium hexafluorophosphate (Iod) and ethyl dimethylaminobenzoate (EDB). The absorption, luminescence, and redox properties of nickel complexes and ligands were explored and compared for a better understanding of their structure/reactivity relationship. The designed nickel complexes showed good photoinitiation abilities. NiL2 exhibited the highest monomer conversion, and it was investigated in the on-off process under green light irradiation, demonstrating the efficiency of the system in reactivating the polymerization process. An oxidative pathway mechanism was proposed based on free energy, steady state photolysis and electron spin resonance spin trapping experiments. The best system was successfully applied in cationic photopolymerization and 3D printing. (AU)

• Processo FAPESP: 21/13128-1 - Desenvolvimento de novos materiais poliméricos via acoplamento de reações mecanisticamente incompatíveis usando catalisadores heterobimetálicos de Ru/Pd e Ru/Ni
• Beneficiário: Valdemiro Pereira de Carvalho Júnior
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 21/11873-1 - Complexos organometálicos de Mn(II), Fe(II) e Ni(II) como fotocatalisadores redox da CRP2: nova estratégia para fotopolimerização com LEDs
• Beneficiário: Beatriz Eleutério Goi Carvalho
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 21/11741-8 - Desenvolvimento de novos complexos de Ni(II) para reações de fotopolimerização radicalar controlada (foto-OMRP e CRP2) e aplicação em impressão 3D
• Beneficiário: Naralyne Martins Pesqueira
• Modalidade de apoio: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 22/16213-2 - Fotopolimerização radicalar controlada (CRP2) e aplicação em impressão 3D usando novos complexos de Ni(II)
• Beneficiário: Naralyne Martins Pesqueira
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Doutorado Direto