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Reactive bay functionalized perylene monoimide-polyhedral oligomeric silsesquioxane organic electronic dye

Wangatia L. M., Sun B., Zeng T., Zhu M.

Materials Science Poland

2015

Vol. 33, No. 1

113--121

Aggregation-induced quenching is particularly detrimental in perylene diimides, which are characterized by a near-unity fluorescence quantum yield in solution but are far less emissive in the solid state. Previously, perylene diimide has been improved by linking it to the inorganic cage of polyhedral oligomeric silsesquioxanes. As a further study on perylene diimidepolyhedral oligomeric silsesquioxanes, we report on a double functionalized molecular structure, which can be used for substitution at the bay area and as a side group in other materials. Typical solution absorption and emission features of the perylene diimide fragment have been observed in this new reactive perylene diimide-polyhedral oligomeric silsesquioxane. Moreover, reduced stacking during aggregation and spherical particles exhibiting solid fluorescence have been obtained. Organic semiconducting material with enhanced solid state photophysical properties, like solid fluorescence is a subject of great interest owing to its possible high-tech applications in optoelectronic devices.

Multiblock segmented polyurethanes and polyurethane-ureas based on poly(ethylene oxide)/poly(propylene oxide)/poly(ethylene oxide) macrodiols. Synthesis and characterization

Filip D., Macocinschi D., Ioanid E., Vlad S.

Polimery

2010

T. 55, nr 5

358-365

The amphiphilic behavior of poly(ethylene oxide)/poly(propylene oxide)/poly(ethylene oxide) block copolymers has been broadened by introducing new urethane-urea as well as poly(ethylene glycol) co-segments in polyurethane (PUR) and polyurethane-ureas (PURU) materials. Supermolecular organization and self-assembly was confirmed by electron microscopy transmission observations. The driving force for self-assembling is represented by the amphiphilic nature of these materials, the interactional segment length and stabilization through hydrogen bonding. FT-IR spectroscopy was used to investigate the hydrogen bonding related to phase segregation. Phase transitions and phase segregation was evidenced by DSC analyses. The relationship between structure and thermal stability was investigated by thermogravimetric analysis.

Opisano sposób syntezy amfifilowych multiblokowych poliuretanów (PUR) i poliuretano-moczników (PURU) w wyniku wprowadzenia odpowiednich segmentów do łańcucha wymienionych w tytule makrodioli. Scharakteryzowano skład, strukturę oraz wartości Mw i Mw/Mn (tabela 1) uzyskanych PUR (2 typy) oraz PURU (również 2 typy). Przedyskutowano i porównano wyniki ich badania metodami FT-IR (rys. 5), derywatograficzną (rys. 1 i 2), różnicowej analizy termicznej (DSC, rys. 3, tabela 1), rentgenograficzną (rys. 4) i elektronowej mikroskopii transmisyjnej (rys. 6). Zinterpretowano zdolność do samorzutnego tworzenia agregatów przez opisywane produkty, wiążąc ją przede wszystkim z ich amfifilowym charakterem oraz stabilizacją poprzez wiązanie wodorowe. Wyniki uzyskane metodami DSC i FT-IR posłużyły do wyjaśnienia przebiegu zjawisk segregacji fazowej a także przemian fazowych.