| タイトル | Silsesquioxanes as precursors to ceramic composites |
| 本文（外部サイト） | http://hdl.handle.net/2060/19870015999 |
| 著者（英） | Hyatt, Lizbeth H.; Damore, Lisa; Gorecki, Joy; Hurwitz, Frances I. |
| 著者所属（英） | NASA Lewis Research Center |
| 発行日 | 1987-01-01 |
| 言語 | eng |
| 内容記述 | Silsesquioxanes having the general structure RSiO sub 1.5, where R = methyl, propyl, or phenyl, melt flow at 70 to 100 C. Above 100 C, free -OH groups condense. At 225 C further crosslinking occurs, and the materials form thermosets. Pyrolysis, with accompanying loss of volatiles, takes place at nominally 525 C. At higher temperatures, the R group serves as an internal carbon soruce for carbo-thermal reduction to SiC accompanied by the evolution of CO. By blending silsesquioxanes with varying R groups, both the melt rheology and composition of the fired ceramic can be controlled. Fibers can be spun from the melt which are stable in argon in 1400 C. The silsesquioxanes also were used as matrix precursors for Nicalon and alpha-SiC platelet reinforced composites. |
| NASA分類 | COMPOSITE MATERIALS |
| レポートNO | 87N25432
NASA-TM-89893
E-3581
NAS 1.15:89893 |
| 権利 | No Copyright |
| URI | https://repository.exst.jaxa.jp/dspace/handle/a-is/149863 |
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