Preparation and characterization of aryl-substituted polysilsesquioxanes

Technical Report · Tue Sep 01 04:00:00 EDT 1998

DOI:https://doi.org/10.2172/672121· OSTI ID:672121

Schneider, D A; Loy, D A; Baugher, B M; Wheeler, D R; Assink, R A; Alam, T M; Saunders, R

Polymerizations of aryltrialkoxysilanes generally afford soluble oligomeric or polymeric aryl-substituted silsesquioxanes. This is in spite of being based on trifunctional precursors capable of forming highly crosslinked and insoluble network polymers. In this study, soluble phenyl, benzyl, and phenethyl-substituted silsesquioxane oligomers and polymers were prepared by hydrolyzing their respective triethoxysilyl precursor with water or aqueous acid. Additional samples of the polymers were prepared by heating the materials at 100 C or 200 C under vacuum in order to drive the condensation chemistry. One sample of polybenzylsilsesquioxane was heated at 200 C with catalytic NaOH. The resulting materials were characterized using solution {sup 1}H, {sup 13}C, and {sup 29}Si NMR spectroscopy, gel permeation chromatography, and differential scanning calorimetry. Of particular interest was the effect of the aryl substituent, and processing conditions on the molecular weight and glass transition temperatures of the polysilsesquioxanes.

• Research Organization: Sandia National Labs., Albuquerque, NM (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 672121
• Report Number(s): SAND--98-1421C; CONF-980405--; ON: DE98003551; BR: DP0102031
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ARYL RADICALS
DEHYDROCYCLIZATION
EXPERIMENTAL DATA
HYDROLYSIS
MOLECULAR STRUCTURE
MOLECULAR WEIGHT
NUCLEAR MAGNETIC RESONANCE
POLYMERIZATION
SILOXANES