Synthesis, structure and thermogravimetric analysis of α,ω-telechelic polydimethylsiloxanes of low molecular weight

Autor: Tasić Aleksandra M., Pergal Marija V., Antić Mališa P., Antić Vesna V.
Jazyk: angličtina
Rok vydání: 2017
Předmět:
Zdroj: Journal of the Serbian Chemical Society, Vol 82, Iss 12, Pp 1395-1416 (2017)
Druh dokumentu: article
ISSN: 0352-5139
1820-7421
DOI: 10.2298/JSC170427082T
Popis: A series of α,ω-telechelic polydimethylsiloxanes (PDMS), with predetermined molecular weights of about 2500 g mol-1, was synthesized by siloxane equilibration reaction. Syntheses were performed using octamethylcyclotetrasiloxane (D4) and various disiloxanes: hexamethyldisiloxane (HMDS), 1,1,3,3-tetramethyldisiloxane (TMDS), 1,3-divinyltetramethyldisiloxane (DVTMDS), 1,3-bis(3-carboxypropyl)tetramethyldisiloxane (DCPTMDS) and 1,3-bis(3-aminopropyl)tetramethyldisiloxane (DAPTMDS). The role of the disiloxane was to introduce terminal functional groups at the end of the polymer chains and to control the molecular weight of the polymers. Polymers with trimethyl, hydrido, vinyl, carboxypropyl and aminopropyl end-groups were obtained in this way. The structure of the α,ω-telechelic PDMSs was confirmed by NMR and IR spectroscopy. The molecular weights of the polymers were determined by 1H-NMR, gel permeation chromatography (GPC) and dilute solution viscometry. Thermogravimetric analysis (TGA) under nitrogen and air showed that the type of the terminal groups significantly influenced the thermal and thermo-oxidative stability, as well as the degradation mechanism of the α,ω-telechelic PDMSs. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 172062]
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