caa a22 4500 463190815 CHVBK 20180406164908.0 cr unu---uuuuu 170326e20070701xx s 000 0 eng 10.1007/s10973-005-7323-2 doi (NATIONALLICENCE)springer-10.1007/s10973-005-7323-2 Thermodynamics of polymethylhydrosiloxane based on 1,3,5,7-tetramethyl-1,3,5,7-tetrahydrocyclotetrasiloxane [Elektronische Daten] [N. Smirnova, L. Tsvetkova, B. Lebedev, B. Zavin, V. Kotov] In an adiabatic vacuum calorimeter the temperature dependence of the heat capacity C p 0 of 1,3,5,7-tetramethyl-1,3,5,7-tetrahydrocyclotetrasiloxane and polymethylhydrosiloxane on its basis was measured between 6 and 350 K mainly with accuracy of about 0.2%. Two-phase transitions corresponding, probably, to the fusion of cis-and trans-conformations of the monomer as well as the glass transition of the polymer were detected. The results obtained were used to calculate the thermodynamic functions C p 0 , H 0(T)-H 0(0), S 0(T), G 0(T)-H 0(0) of the monomer and polymer in the range from T→0 to T=340 K, and to estimate the zero entropy S 0(0) of amorphous polymer. Standard entropies of formation ΔS f 0 of the tested monomer and polymer at T=298.15 K as well as the entropy of synthesis of polymethylhydrosiloxane from 1,3,5,7-tetramethyl-1,3,5,7-tetrahydrocyclotetrasiloxane over the range from T→0 to 340 K were estimated. The value of fractal dimension D in the heat capacity function of the multifractal variant of the Debye's theory of heat capacity was found to be 1.5 for polymer in the 18-35 K range, that testifies to its layer-chain structure. Springer Science+Business Media LLC, 2007 calorimetry nationallicence polymerization nationallicence polymethylhydrosiloxane nationallicence 1,3,5,7-tetramethyl-1,3,5,7-tetrahydrocyclotetrasiloxane nationallicence thermodynamic parameters nationallicence Smirnova N. Chemistry Institute, Nizhny Novgorod State University, Nizhny Novgorod, Russia aut Tsvetkova L. Chemistry Institute, Nizhny Novgorod State University, Nizhny Novgorod, Russia aut Lebedev B. aut Zavin B. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow, Russia aut Kotov V. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow, Russia aut Journal of Thermal Analysis and Calorimetry Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 89/1(2007-07-01), 217-222 1388-6150 89:1<217 2007 89 10973 https://doi.org/10.1007/s10973-005-7323-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10973-005-7323-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Smirnova N. Chemistry Institute, Nizhny Novgorod State University, Nizhny Novgorod, Russia aut NATIONALLICENCE 700 1- Tsvetkova L. Chemistry Institute, Nizhny Novgorod State University, Nizhny Novgorod, Russia aut NATIONALLICENCE 700 1- Lebedev B. aut NATIONALLICENCE 700 1- Zavin B. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow, Russia aut NATIONALLICENCE 700 1- Kotov V. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, Moscow, Russia aut NATIONALLICENCE 773 0- Journal of Thermal Analysis and Calorimetry Kluwer Academic Publishers-Plenum Publishers; http://www.springer-ny.com 89/1(2007-07-01), 217-222 1388-6150 89:1<217 2007 89 10973 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer