Efficacy analysis of new copper complex for visible light (455, 530 nm) radical/cationic photopolymerization: The synergic effects and catalytic cycle

PLoS One. 2022 Jul 26;17(7):e0270679. doi: 10.1371/journal.pone.0270679. eCollection 2022.

Abstract

The kinetics and the conversion features of two 3-component systems (A/B/N), based on the proposed new kinetic schemes of Mokbel and Mau et al, in which a visible LED is used to excite a copper complex to its excited triplet state (G*). The coupling of G* with iodonium salt and ethyl 4-(dimethylamino)benzoate (EDB) produces both free radical polymerization (FRP) of acrylates and the free radical promoted cationic polymerization (CP) of epoxides using various new copper complex as the initiator. Higher FRP and CP conversion can be achieved by co-additive of [B] and N, via the dual function of (i) regeneration [A], and (ii) generation of extra radicals. The interpenetrated polymer network (IPN) capable of initiating both FRP and CP in a blend of TMPTA and EPOX. The synergic effects due to CP include: (i) CP can increase viscosity limiting the diffusional oxygen replenishment; (ii) the cation also acts as a diluting agent for the IPN network, and (iii) the exothermic property of the CP. The catalytic cycle, synergic effects, and the oxygen inhibition are theoretically confirmed to support the experimental hypothesis. The measured results of Mokbel and Mau et al are well analyzed and matching the predicted features of our modeling.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cations
  • Copper*
  • Free Radicals
  • Light*
  • Oxygen
  • Polymers

Substances

  • Cations
  • Free Radicals
  • Polymers
  • Copper
  • Oxygen

Grants and funding

This study was supported by the Agence Nationale de la Recherche (ANR agency) in the form of the NoPerox grant. The China Medical University provided support in the form of a grant to DCC [CMU110-ASIA-11]. The New Photon Corp provided support in the form of a salary to JTL. The specific roles of these authors are articulated in the ‘author contributions’ section. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.