ИСТИНА

Liquid organic luminophores are π-conjugated luminophores with covalently attached bulky, flexible and low-melting side substituents [1]. They are relatively new and class of materials, which have high processability owing to their fluidic nature and efficient fluorescence in pristine state. However, the structure-property relationships of such compounds remain poorly understood. In addition, they exhibit luminescence in a limited short-wavelength region of the spectrum. Most of the molecules with long wavelength or NIR absorption and luminescence have a rigid planar structure due to their large π-conjugationt. In the course of this work, the series of novel liquid benzothiadiazole-based linear and branched luminophores containing phenylene or thiophene units, emitting light in various ranges of the visible spectrum, were synthesized. To liquefy these olygomers the trihexylsilyl terminal substituent as most effective solubilizing group, which was identifying in our previous work [2]. The high purity and specified structure of all the compounds obtained was proved by a complex of modern research methods. The influence of the nature, length, branching and type of π-conjugated core on the optical properties, rheology, phase behavior and thermal stability of luminophores has been studied. Some of the obtained oligomers were tested as scintillation detectors. Due to the high concentration of active phosphor fragments per unit volume in such materials, which cannot be achieved by preparing a simple solution based on them, and the relatively high fluorescence quantum yield in the block (up to 75%), effective scintillators based on these oligomers were created. This work was supported by the grant of the President of the Russian Federation (title 3843.2022.1.3).