Thermal softening behavior of poly (phenylsilsesquioxane) and poly (benzylsilsesquioxane) particles

Citation
A. Matsuda et al., Thermal softening behavior of poly (phenylsilsesquioxane) and poly (benzylsilsesquioxane) particles, J CERAM S J, 108(9), 2000, pp. 830-835
Citations number
9
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Material Science & Engineering
Journal title
JOURNAL OF THE CERAMIC SOCIETY OF JAPAN
ISSN journal
0914-5400 → ACNP
Volume
108
Issue
9
Year of publication
2000
Pages
830 - 835
Database
ISI
SICI code
0914-5400(200009)108:9<830:TSBOP(>2.0.ZU;2-P
Abstract
The thermal softening behavior of poly(phenylsilsesquioxane) (PhSiO3/2) and paly(benzylsilsesquioxane) (BnSiO3/2) particles during heat treatment has been investigated from the results of gel permeation chromatography, therma l and structural analyses of the particles. Both PhSiO3/2 and BnSiO3/2 part icles thermally softened, and the on-set temperature of thermal sintering w as about 140 and 50 degrees C for PhSiO3/2 and BnSiO3/2. respectively. The thermal sintering of the PhSiO3/2 and BnSiO3/2 particles was caused by the decrease of viscosity at temperatures higher than the glass transition temp eratures. Glass transition was observed for BnSiO3/2 in the repeated heatin g runs, while for PhSiO3/2 glass transition was appreciable only in the fir st heating run. From Si-29 nuclear magnetic resonance spectra, the developm ent of siloxane network during heat treatment was found to be more signific ant in PhSiO3/2 than in BnSiO3/2. The difference in the structural evolutio n during heat treatment makes PhSiO3/2 particles thermosetting and BnSiO3/2 ones thermoplastic.