1. Institut de Science des Matériaux de Mulhouse (IS2M), UMR CNRS 7361, Mulhouse, CEDEX, France;2. Institut de Chimie et des Matériaux Paris‐Est (ICMPE), UMR CNRS 7182, Université Paris‐Est Créteil (UPEC), Thiais, France;3. Departamento di Quimica Fisica, Universidad de Murcia, Murcia, Spain;4. Formerly, ENSCMu‐UHA, Mulhouse, CEDEX, France
Abstract:
Titanium propoxide, titanium isopropoxide, and titanium (triethanolaminato) isopropoxide are proposed as high‐performance additives to overcome the oxygen inhibition effects in the free radical photopolymerization of a low‐viscosity monomer thin film, under air and upon a low‐intensity UV light activation. Indeed, when added to a Type I photoinitiator such as bis(2,4,6‐trimethylbenzoyl)‐phenylphosphine oxide (BAPO), noticeably higher conversions are achieved under air (48% vs. 30%). The in situ formation of Ti‐based nanoparticles is also observed. The photochemical properties of these types of Ti‐based compounds as well as their interaction with BAPO are investigated by steady‐state photolysis and electron spin resonance. Molecular orbital calculations give an interesting insight into the possible reactions. A chemical mechanism is also proposed.
