22.10.2024 Photocuring of aqueous and solvent free coating comprising nanoparticles with new photonic technique of polymerization Back Tools Bookmark Share Photonic techniques have received increasing importance for physical and chemical drying of coatings. This can be considered as a green alternative to save huge amounts on energy. High-power NIR-LEDs emitting between 750-1100 nm have gained attention compared to well established UV systems, this can be seen in longer excitation wavelength facilitating deeper penetration into the sample and the possibility for photocuring of components absorbing in the UV and visible range. Cyanines derived from heptamethines carrying a special conjugate pattern serve as NIR-sensitizers. These materials can facilitate generation of radicals and conjugate acid to initiate both free radical and cationic photopolymerization, respectively. Moreover, heat released by the sensitizer facilitates physical drying of the coatings, which is shown by physical drying of water-based PU dispersions and photocuring of epoxides comprising silane functionalized sol-gel formulations combined with iodonium salts. Polymer films obtained exhibited higher glass transition (Tg) applying NIR exposure compared to those photocured by UV radiation. DMA and contact angle measurements support experimental findings. Duration: 19:30Speaker: Qunying WangCompany: Niederrhein University of Applied SciencesConference: ECS ConferenceLocation: NurembergDate: 26.03.2023