Sensitized Photopolymerization of an Ionic Liquid-Based Monomer by Using CdTe Nanocrystals

Semiconductor nanocrystal has been demonstrated as a photosensitizer for the photopolymerization of acrylic monomer in combination with an onium salt coinitiator. An acrylic monomer designed based on ionic liquid was able to dissolve both coinitiator and cationic CdTe nanocrystals and polymerized by visible irradiation. Since the onium salt has no sensitivity in the visible region, the polymerization occurred by the indirect activation of coinitiator. Emission quenching study of CdTe nanocrystals with the coinitiator and electrochemical studies on them revealed that the polymerization was initiated by the photoinduced electron transfer from the CdTe nanocrystal to the onium salt. The polymerization kinetics was compared with the organic dye sensitized photopolymerization system by monitoring the conversion of monomer with FT-IR. The large extinction coefficient and long excitation lifetime of CdTe nanocrystals were considered to be responsible for the efficient electron transfer with onium salt and the ef...