TY - JOUR
T1 - Effect of solvent type on polycondensation of TEOS catalyzed by DBTL as used for stone consolidation
AU - Salazar-Hernández, Carmen
AU - Zárraga, Ramón
AU - Alonso, Sergio
AU - Sugita, Satoshi
AU - Calixto, Sergio
AU - Cervantes, Jorge
N1 - Funding Information:
Acknowledgments The authors wish to acknowledge the financial support of the Consejo Nacional de Ciencia y Tecnología (CONA-CYT-Mexico) through grant SEP-CONACYT 25397.
PY - 2009/3
Y1 - 2009/3
N2 - We have investigated the effect of solvent in the sol-gel process of tetraethylorthosilicate (TEOS) when di-n-butyltin dilaurate (DBTL) is used as polycondensation catalyst. Two sets of materials similar to those employed in the field of stone consolidation were prepared in the laboratory by using either protic or aprotic solvents: (1) xerogels from TEOS/DBTL, and (2) composites from TEOS/colloidal silica particles/DBTL. The results have shown that the solvent directly influences the aggregation pathway of the condensates. For a mixture of methyl ethyl ketone/acetone (aprotic solvents), gels with a higher degree of condensation were obtained. In the case of TEOS xerogels, the materials are essentially non-porous. Additionally, the incorporation of colloidal silica particles induces an important increase in porosity, which is even more dramatic when ethanol is used as solvent, through the formation of micro and mesoporous materials as the concentration of particles is increased. A TEOS polymerization pathway is suggested depending on which system of solvents is used. Various analytical techniques were used to characterize the materials obtained.
AB - We have investigated the effect of solvent in the sol-gel process of tetraethylorthosilicate (TEOS) when di-n-butyltin dilaurate (DBTL) is used as polycondensation catalyst. Two sets of materials similar to those employed in the field of stone consolidation were prepared in the laboratory by using either protic or aprotic solvents: (1) xerogels from TEOS/DBTL, and (2) composites from TEOS/colloidal silica particles/DBTL. The results have shown that the solvent directly influences the aggregation pathway of the condensates. For a mixture of methyl ethyl ketone/acetone (aprotic solvents), gels with a higher degree of condensation were obtained. In the case of TEOS xerogels, the materials are essentially non-porous. Additionally, the incorporation of colloidal silica particles induces an important increase in porosity, which is even more dramatic when ethanol is used as solvent, through the formation of micro and mesoporous materials as the concentration of particles is increased. A TEOS polymerization pathway is suggested depending on which system of solvents is used. Various analytical techniques were used to characterize the materials obtained.
KW - Composites
KW - DBTL
KW - Solvent effect
KW - Stone consolidation
KW - TEOS
UR - http://www.scopus.com/inward/record.url?scp=60049098355&partnerID=8YFLogxK
U2 - 10.1007/s10971-008-1879-9
DO - 10.1007/s10971-008-1879-9
M3 - Artículo
SN - 0928-0707
VL - 49
SP - 301
EP - 310
JO - Journal of Sol-Gel Science and Technology
JF - Journal of Sol-Gel Science and Technology
IS - 3
ER -