Two Routes Towards Photoinitiator-Free Photopolymerization in Miniemulsion: Acrylate Self-Initiation and Photoactive Surfactant

摘要

Two novel photoinitiator-free approaches to photopolymerize acrylic monomers with a conventional Hg lamp starting from an acrylates monomer miniemulsion are investigated. In one system the acrylate nanodroplet reaction is self-initiated and in the other the use of a photoactive diphenyl ether surfactant yields phenyl and phenoxyl initiating radicals upon UV irradiation. Photopolymerization kinetics are monitored in situ by real-time Fourier transform near infrared spectroscopy (RT-FTNIR) and the colloidal properties are systematically investigated by dynamic light scattering (DLS). The up-scaling of these PI-free miniemulsion photopolymerizations is carried out in an annular photoreactor.