1254475-08-5Relevant academic research and scientific papers
Peripherally aromatic silsesquioxanes featuring reactive functionality: synthesis and applications thereof
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Page/Page column 6; 7, (2015/03/28)
Novel POSS mono- and dianiline compounds, their synthesis procedures, and applications in host materials for the purposes of property enhancement are described. This class of POSS compounds features completely aromatic peripheries and partial amine functi
Identification and quantification of cis and trans isomers in aminophenyl double-decker silsesquioxanes using 1H-29Si gHMBC NMR
Schoen,Holmes,Lee
, p. 490 - 496 (2013/07/26)
Cis and trans isomers of a series of double-decker silsesquioxanes (DDSQ) were characterized by two-dimensional NMR techniques. The 1H NMR spectra of these species have not previously been assigned to a degree that allows for quantification. Thus, 1H-29Si HMBC correlations were applied to facilitate 1H spectral assignment and also to confirm previous 29Si assignments for this class of silsesquioxanes. With the ability to identify all the pertinent resonances of the 1H NMR spectrum, 29Si NMR is no longer required for quantification and required only for characterization. This not only saves time and material but also provides a more accurate quantification, thus allowing for the ratio of cis and trans isomers present in each compound to be determined. A more accurate measure of the cis/trans ratio enables the investigation of its influence on the physical and chemical properties of DDSQ nanostructured materials. Copyright
Thermal transitions and reaction kinetics of polyhederal silsesquioxane containing phenylethynylphthalimides
Seurer, Bradley,Vij, Vandana,Haddad, Timothy,Mabry, Joseph M.,Lee, Andre
scheme or table, p. 9337 - 9347 (2011/11/29)
Thermal transitions and reaction kinetics of polyhedral oligomeric silsesquioxane (POSS) with phenylethynylphthalimide (PEPI) moieties were investigated. Specifically, this study was designed to probe the influence of the POSS peripheries, types of spacer group in between the PEPI and the SiO 1.5 core, the architecture of the PEPI arrangement with respect to the SiO1.5 core, and the number of PEPI groups per cage on the thermal transitions and the cross-linking reaction of phenylethynyl. PEPI-POSS compounds with isobutyl peripheries exhibited lower melting temperatures as compared to those with phenyl periphery, consequently these isobutyl PEPI-POSS derivatives have a higher phenylethynyl reaction rate, although the onset of reaction temperature was not significantly affected. Changing the spacer group from propyl to phenyl causes an increase in the melting transition temperature along with a higher heat of fusion at melting; however, the more rigid phenyl spacer enables the PEPI-POSS to form a higher degree of crystallinity upon cooling. The more rigid phenyl spacer also initiates the polyene reactions at lower temperatures. For POSS with PEPI attached to either side of the cage, there are two isomers with respect to the SiO1.5 core. This mixture of two isomers inhibits the formation of crystallinity as compared with the "pendent" derivative where both PEPI groups come off from the same corner of POSS cage. Finally, it was found that these PEPI-POSS molecules have reaction kinetics and onset temperatures on par with organic hexafluorophenylethynyl oligoimides, which make these PEPI-POSS molecules excellent candidates as nanocomposite additives in high performance composite applications.
