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A Study of the Polycondensation of (Tetrahydroxy)(Tetraaryl)Cyclotetrasiloxanes under Equilibrium and Non-Equilibrium Conditions in the Presence and Absence of Montmorillonite.

ABSTRACT: Oligo- and polycyclosiloxanes were obtained by the polycondensation of (tetrahydroxy)(tetraaryl)cyclotetrasiloxanes in equilibrium and non-equilibrium conditions in the presence and absence of montmorillonite (MMT). Their composition and the structures of their components were investigated by infrared (IR) spectroscopy, 29Si nuclear magnetic resonance (NMR) spectroscopy, atmospheric pressure chemical ionization (APCI) mass spectrometry, powder X-ray diffraction (XRD), and gel-penetrating chromatography (GPC). Also, a comparison of polymers formed in the presence of MMT and via anionic polymerization was performed showing differences in their structures.

SUBMITTER: Makarova NN

PROVIDER: S-EPMC6415273 | biostudies-literature | 2018 Apr

REPOSITORIES: biostudies-literature

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A Study of the Polycondensation of (Tetrahydroxy)(Tetraaryl)Cyclotetrasiloxanes under Equilibrium and Non-Equilibrium Conditions in the Presence and Absence of Montmorillonite.

Makarova Nataliya N NN Lyakhovetsky Yury I YI Petrova Irina M IM Dolgushin Fedor M FM Ikonnikov Nikolai S NS Peregudov Alexander S AS Strelkova Tatyana V TV Klemenkova Zinaida S ZS

Polymers 20180409 4

Oligo- and polycyclosiloxanes were obtained by the polycondensation of (tetrahydroxy)(tetraaryl)cyclotetrasiloxanes in equilibrium and non-equilibrium conditions in the presence and absence of montmorillonite (MMT). Their composition and the structures of their components were investigated by infrared (IR) spectroscopy, <sup>29</sup>Si nuclear magnetic resonance (NMR) spectroscopy, atmospheric pressure chemical ionization (APCI) mass spectrometry, powder X-ray diffraction (XRD), and gel-penetrat ...[more]

PMID: 30966457

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