New photoinitiating systems based on boron-dipyrromethene dye (bodipy)/iodonium salt and optionally tris(trimethylsilyl)silane are proposed for the polymerization of divinylether and epoxy monomers upon visible-light exposure. The presence of the silane increases the epoxide rate of polymerization and conversion. Using acrylate/vinyl ether blends, the synthesis of cross-linked polymer networks (possessing two T g values: −11 and 111 °C) is also successfully achieved through concomitant cationic and radical polymerization pathways. The chemical mechanisms associated with these initiating systems are investigated by steady-state photolysis and ESR experiments.

International audience1,3-Bis(dicyanomethylidene)indane is presented as a new initiator for ring opening polymerization of epoxides at RT. This compound behaves as a strong acid (AH) with an associated basic form (A ) that does not inhibit the propagation of the cationic polymerization. Remarkably, A is characterized by a strong visible light absorption and can also photosensitize iodonium salt decomposition. A new iodonium salt based on A as a counter-anion is proposed. This latter compound exhibits unusual properties: (i) excellent absorption in the 300-700 nm wavelength range and (ii) a free radical initiating ability for l > 300 nm. The chemical mechanisms are investigated by ESR, fluorescence and steady state photolysis experiment

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