Photoinitiators Derived From Natural Product Scaffolds: Mono-Chalcones in Three-Component Photoinitiating Systems and their Applications in 3D Printing

Jacques Lalevee (1) , Hong Chen (1) , Guillaume Noirbent (2) , Ke Sun (1) , Damien Brunel (2) , Didier Gigmes (2) , Fabrice Morlet-Savary (1) , Yijun Zhang (3) , Shaohui Liu (1) , Pu Xiao (4) , Frederic Dumur (2) , Jacques Lalevée

1 IS2M - Institut de Science des Matériaux de Mulhouse
2 ICR - Institut de Chimie Radicalaire
3 Department of Materials Science and Engineering
4 ANU - Australian National University

The design and development of high-performance photoinitiating systems applicable to visible light delivered from light-emitting diodes (LEDs) attracts an ever-increasing attention due to their great potential applications in various fields. Chalcones correspond to a well-established class of natural compounds present in many plants. In this context, photoinitiators based on the scaffolds of natural compounds have probably a great potential to open the way for non-toxic photoinitiators in the manufacture of biocompatible polymer materials. In this work, 23 different chalcones selected from in-silico molecular design (i.e. through molecular orbital calculations) are used in conjunction with an amine i.e. ethyl 4-(dimethylamino) benzoate (EDB) and an iodonium salt (bis-(4-tert-butylphenyl)iodonium hexafluorophosphate, Iod) to form photoinitiating systems (PISs) capable to initiate the polymerization of polyethylene glycol (600) diacrylate (PEG-diacrylate) via an oxidation-reduction reaction mechanism. The formation of hydrogels by photopolymerization of PEG-acrylate is found very efficient. Remarkably, 10 of the 23 Chalcones are completely new and even never synthesized prior to this work (Chalcone 4, 5, 7, 8, 9, 10, 12, 15, 16 and 21). By using computational quantum chemistry, fluorescence, steady-state photolysis, and electron spin resonance spin-trapping techniques, the photoinitiation mechanism of three-component photoinitiating systems based on chalcones/Iod/EDB are clarified. The results demonstrate that several chalcones-based PISs can initiate the free radical photopolymerization. Moreover, the developed chalcone-based three-component systems are applied to generate 3D hydrogel patterns using the 3D laser write technology. This research represents some novel insights into photopolymerization reactions with three-component photoinitiating systems used for 3D printing of hydrogels.

Mots clés: chalcone; Claisen Schmidt condensation; free radical polymerization; three-component photoinitiating system; 3D printing

Domaines: Matériaux

Jacques Lalevee, Hong Chen, Guillaume Noirbent, Ke Sun, Damien Brunel, et al.. Photoinitiators Derived From Natural Product Scaffolds: Mono-Chalcones in Three-Component Photoinitiating Systems and their Applications in 3D Printing. Polymer Chemistry, 2020, 11 (28), pp.4647-4659. ⟨10.1039/D0PY00568A⟩. ⟨hal-02906501⟩