Copy the page URI to the clipboard
El Aziz, Youssef; Bassindale, Alan R.; Taylor, Peter G.; Stephenson, Richard A.; Hursthouse, Michael B.; Harrington, Ross W. and Clegg, William
(2013).
DOI: https://doi.org/10.1021/ma302229v
Abstract
The homologous series of octa-n-alkylsilsesquioxanes (n-alkylPOSS) was prepared by hydrosilylation of octahydrido-octasilsesquioxane H8T8 with terminal n-alkenes in good yields (n = 2–18). The compounds were characterized by NMR spectroscopy (1H, 13C, 29Si), MALDI-TOF and ESI MS. Most of them have also been characterized using X-ray crystallography, including some polymorphs. The packing systems of the octa-n-alkylsilsesquioxanes are reported. Two types of packing have been observed, rod-like and disk-like (interdigitated). Some n-alkylPOSS crystals were formed in which the chains are tilted away from the axes of the cubic core. It was also observed that as alkyl-chains are flexible they can take up a variety of conformations. Melting points of the homologous series showed an odd-even alternating effect for alkyl chains longer than four CH2 units. The TGA of n-alkylPOSS under nitrogen showed that the thermal stability temperatures are between 200 and 400 °C. Pyrolysis-gas chromatography/mass spectrometry has been used to elucidate the thermal degradation process of T8(n-CnH2n+1)8 (n = 11 and 18). Thermal cracking along the whole alkyl chain was observed rather than simple loss of the complete arm.
Viewing alternatives
Metrics
Public Attention
Altmetrics from AltmetricNumber of Citations
Citations from DimensionsItem Actions
Export
About
- Item ORO ID
- 35986
- Item Type
- Journal Item
- ISSN
- 1520-5835
- Academic Unit or School
-
Faculty of Science, Technology, Engineering and Mathematics (STEM) > Life, Health and Chemical Sciences
Faculty of Science, Technology, Engineering and Mathematics (STEM) - Copyright Holders
- © 2013 American Chemical Society
- Related URLs
- Depositing User
- Peter Taylor