Field of Expertise: Advanced Material Science | |
Dye functionalized Polymer architectures Incoherent up-conversion of Photons by sensitized Triplet-Triplet-Annihilation (TTA) of emitter molecules is a relatively efficient process to transfer electromagnetic radiation of low energy into higher energies (e.g., near-infrared to visible radiation). In a first step a sensitizer molecule is excited (e.g., by sunlight) into its singlet state that quickly relaxes into a metastable triplet state by intersystem crossing. In presence of suitable emitter molecules that have triplet levels of similar energy a Triplet-Triplet-Energy-Transfer from the sensitizer to the emitter takes place, followed by TTA of two adjacent emitter triplets and radiative emission of a photon of higher energy compared to the absorbed ones. Thus, for efficient TTA-processes in a polymeric material, two suitable dye molecules have to be incorporated in suitable concentrations and with optimum distances between both. This can be easily achieved by controlled co-polymerization of dye-functionalized monomers with matrix monomers. We focus in this contribution of the preparation of new dye functionalized monomers based on norbornene as basic monomeric unit. Using ring opening metathesis polymerization (ROMP), designed statistical as well as block copolymers can be prepared. |