TY - JOUR
T1 - Arylene- and alkylene-bridged polysilsesquioxanes
AU - Small, James H.
AU - Shea, Kenneth J.
AU - Loy, Douglas A.
N1 - Funding Information:
National Science Foundation and the Air Force
Funding Information:
for financial support. This research was also par-
PY - 1993/8/1
Y1 - 1993/8/1
N2 - Bis(triethoxysilyl)arylene monomers 1-5 and the 1,6-bis(trimethoxysilyl)hexylene monomer 6 were hydrolytically condensed under sol-gel conditions using both acid and base catalysts to produce their respective arylene- and alkylene-bridged polysilsesquioxane materials (X-1 through X-6). Polymerization reactions yielded gels within 24 h. One notable exception was the acid-catalyzed polymerization of 2,5-bis(triethoxysilyl)thiophene (X-5-S1) which required approximately 1 month to gel. The gels were processed by extracting with low dielectric solvents or by aqueous extraction. Solid state 13C and 29Si CP MAS-NMR, infrared spectroscopy, and gas sorption porosimetry were measured on the xerogels. The materials were transparent, glass-like xerogels with surface areas as high as 1100 m2/g and porosity primarily confined to a micropore region (< 20 A ̊ diameters). Xerogels prepared using the aqueous extraction had surface areas between 500 and 956 m2/g.
AB - Bis(triethoxysilyl)arylene monomers 1-5 and the 1,6-bis(trimethoxysilyl)hexylene monomer 6 were hydrolytically condensed under sol-gel conditions using both acid and base catalysts to produce their respective arylene- and alkylene-bridged polysilsesquioxane materials (X-1 through X-6). Polymerization reactions yielded gels within 24 h. One notable exception was the acid-catalyzed polymerization of 2,5-bis(triethoxysilyl)thiophene (X-5-S1) which required approximately 1 month to gel. The gels were processed by extracting with low dielectric solvents or by aqueous extraction. Solid state 13C and 29Si CP MAS-NMR, infrared spectroscopy, and gas sorption porosimetry were measured on the xerogels. The materials were transparent, glass-like xerogels with surface areas as high as 1100 m2/g and porosity primarily confined to a micropore region (< 20 A ̊ diameters). Xerogels prepared using the aqueous extraction had surface areas between 500 and 956 m2/g.
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U2 - 10.1016/0022-3093(93)91267-7
DO - 10.1016/0022-3093(93)91267-7
M3 - Article
AN - SCOPUS:0027641690
SN - 0022-3093
VL - 160
SP - 234
EP - 246
JO - Journal of Non-Crystalline Solids
JF - Journal of Non-Crystalline Solids
IS - 3
ER -