Characterization and Some Insights into the Reaction Chemistry of Polymethylsilsesquioxane or Methyl Silicone Resins
Joint Authors
Suto, Michitaka
Itoh, Maki
Auner, Norbert
Oka, Fukuyo
Cook, Simon D.
Source
International Journal of Polymer Science
Issue
Vol. 2012, Issue 2012 (31 Dec. 2012), pp.1-17, 17 p.
Publisher
Hindawi Publishing Corporation
Publication Date
2012-10-18
Country of Publication
Egypt
No. of Pages
17
Main Subjects
Abstract EN
Structural characterization of a polymethylsilsesquioxane (PMSQ) and a DT-type methyl silicone resin (MeDT) has been carried out by various instrumental analyses including GPC, NMR, gas chromatography, and gas chromatography-mass spectrometry.
Although the PMSQ had a Mw around 5000, the resin contained a significant amount of low molecular weight species consisting of T2 [MeSi(OH)O2/2] and T3 [MeSiO3/2] units, ranging from T3 4T2 3 to T3 8T2 2 including many isomers.
One isomer of T3 6T2 2 was isolated of which structure was determined as a cage structure.
The species are supposed to consist mainly of cyclotetra- and cyclopentasiloxanes, but presence of strained rings such as cyclotrisiloxane rings also was suggested.
In MeDT, species in which the T2 units in the molecules from PMSQ is replaced with D2 [Me2SiO2/2] were found, for example, T3 6D2 2, suggesting that general silicone resins consist of similar structures as silsesquioxanes.
The Mark-Houwink exponent for these methyl resins was ~0.3, indicating the molecular shape to be compact.
Investigation on the formation chemistry of the cubic octamers indicates that siloxane bond rearrangement is an important mechanism in the molecule build-up process.
American Psychological Association (APA)
Itoh, Maki& Oka, Fukuyo& Suto, Michitaka& Cook, Simon D.& Auner, Norbert. 2012. Characterization and Some Insights into the Reaction Chemistry of Polymethylsilsesquioxane or Methyl Silicone Resins. International Journal of Polymer Science،Vol. 2012, no. 2012, pp.1-17.
https://search.emarefa.net/detail/BIM-478730
Modern Language Association (MLA)
Itoh, Maki…[et al.]. Characterization and Some Insights into the Reaction Chemistry of Polymethylsilsesquioxane or Methyl Silicone Resins. International Journal of Polymer Science No. 2012 (2012), pp.1-17.
https://search.emarefa.net/detail/BIM-478730
American Medical Association (AMA)
Itoh, Maki& Oka, Fukuyo& Suto, Michitaka& Cook, Simon D.& Auner, Norbert. Characterization and Some Insights into the Reaction Chemistry of Polymethylsilsesquioxane or Methyl Silicone Resins. International Journal of Polymer Science. 2012. Vol. 2012, no. 2012, pp.1-17.
https://search.emarefa.net/detail/BIM-478730
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references
Record ID
BIM-478730