Modulation of the Electronic Properties of 3π-2spiro Compounds Derived from Bridged Oligophenylenes: A Structure–Property Relationship

3π-2spiro compounds are constituted of three π-systems linked through two shared spiro carbons leading to a three-dimensional architecture. The modulation of the electronic properties of such molecular systems can be achieved through the modification and/or substitution of their different π-systems and by the modification of their geometry. The present work is focused on the tuning of the electrochemical properties of a wide range of 3π-2spiro compounds based on fluorenyl, xanthenyl, 2,7-disubstituted fluorenyl, 1,2-<i>b</i>- or 2,1-<i>a-</i>indenofluorenyl, and pentaphenylenyl fragments with a main emphasis on the localization of the successive electron transfers. A detailed structure–property relationship study of interest for the organic electronics scientific community is then drawn

Synthesis and Easy Functionalization of Highly Porous Networks through Exchangeable Fluorines for Target Specific Applications

Synthesis and Easy Functionalization of Highly Porous Networks through Exchangeable Fluorines for Target Specific Application

Multicolor Photoinitiators for Radical and Cationic Polymerization: Monofunctional vs Polyfunctional Thiophene Derivatives

Thiophene and polythiophene derivatives have been prepared and used as photoinitiators upon visible light exposure. Their abilities to initiate, when combined with an iodonium salt (and optionally <i>N</i>-vinylcarbazole), a ring-opening cationic photopolymerization of epoxides and radical photopolymerization of acrylates under various different irradiation sources (i.e., very soft halogen lamp irradiation, laser diode at 405, 457, 473, 532, and 635 nm and blue LED bulb at 462 nm) have been investigated. These systems are characterized by a remarkable performance for purple to red light exposure. They are also particularly efficient for the cationic and radical photopolymerization of an epoxide/acrylate blend in a one-step hybrid cure and lead to the formation of an interpenetrated polymer network IPN (30 s for getting tack-free coatings). Their migration stability is excellent in the cured IPNs. The photochemical mechanisms are studied by steady state photolysis, fluorescence, cyclic voltammetry, electron spin resonance spin trapping, and laser flash photolysis techniques