Developments of Organic-Inorganic Hybrid Free Radical-Cationic Dual Cured Coatings
Résumé
Organic-inorganic nanocomposite hybrid coatings were prepared through a dual-cure process involving free-radical and cationic photopolymerization of a methacrylic-epoxy functionalized resin and subsequent condensation of organo-alkoxysilane inorganic precursor. All the formulations investigated gave rise to photocured films characterized by a high gel content values. A lower decrease on glass transition temperature is observed in the presence of MEMO or GPTS compared with a monofunctional methacrylic monomer. The dual-cured hybrid films were optically transparent evidencing that the organic-inorganic phase separation is in the scale of smaller than 400 nm. The formation of nanometric size inorganic domains (in the range between 10–30 nm), both in the presence of MEMO or GPTS as silica precursor, were further confirmed by TEM analysis