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Thermodynamic Properties of the First-Generation Hybrid Dendrimer with "Carbosilane Core/Phenylene Shell" Structure
Semen S Sologubov1, Alexey V Markin1, Natalia N Smirnova1
1Chemistry Department, National Research Lobachevsky State University of Nizhny Novgorod, 23/5 Gagarin Av., 603950 Nizhny Novgorod, Russia.
Abstract:
The molar heat capacity of the first-generation hybrid dendrimer with a "carbosilane core/phenylene shell" structure was measured for the first time in the temperature range T = 6-600 K using a precise adiabatic vacuum calorimeter and DSC. In the above temperature interval, the glass transition of the studied compound was observed, and its thermodynamic characteristics were determined. The standard thermodynamic functions (the enthalpy, the entropy, and the Gibbs energy) of the hybrid dendrimer were calculated over the range from T = 0 to 600 K using the experimentally determined heat capacity. The standard entropy of formation of the investigated dendrimer was evaluated at T = 298.15 K. The obtained thermodynamic properties of the studied hybrid dendrimer were compared and discussed with the literature data for some of the first-generation organosilicon and pyridylphenylene dendrimers.
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