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Abstract:

The polycondensation of [3-(methacryloxy)propyl]trimethoxysilane was performed in bulk, using 98 wt % formic acid (molar ratio HCOOH/Si = 3 or 6), at 50 or 70°C, for periods of time of up to 1 month. The resulting silsesquioxanes (SSOs) were characterized by 1H NMR, FTIR, SEC, UV-MALDI-TOF MS (linear, reflector, and post-source decay modes), and ESI-TOF MS. The residual concentrations of Si-OCH3 groups, and generated CH3OH and HCOOCH3, were quantitatively monitored by 1H NMR during the initial stage of the synthesis. After 2 days of reaction at 50°C, or about 6 h at 70°C, the resulting SSO mainly contained residual Si-OH groups with only traces of Si-OCH3 groups, as was also confirmed by FTIR and UV-MALDI-TOF MS in the reflector mode. After this time, the polycondensation continued slowly during storage at room temperature, basically through Si-OH + Si-OH reactions. The average fraction of intramolecular cycles increased continuously during the polycondensation. An average value, fav = 0.81, was found for species containing 6-24 Si atoms in a typical reaction product. This evidenced the presence of species with relatively closed structures. In MS/MS spectra, fragmentation of one or more ester groups attached to Si atoms was observed, following a McLafferty rearrangement. The addition of water to the initial formulation (about 3:1 H2O/Si molar ratio) led to a slower polycondensation rate and to a decrease of the average fraction of intramolecular cycles (formation of more open structures). Therefore, the use of 98 wt% formic acid was useful to synthesize SSOs containing a higher fraction of intramolecular cycles than those resulting from conventional formulations.

Registro:

Documento: Artículo
Título:Silsesquioxanes derived from the bulk polycondensation of [3-(methacryloxy)propyl]trimethoxysilane with concentrated formic acid: Evolution of molar mass distributions and fraction of intramolecular cycles
Autor:Eisenberg, P.; Erra-Balsells, R.; Ishikawa, Y.; Lucas, J.C.; Nonami, H.; Williams, R.J.J.
Filiación:Technological Research Center for the Plastics Industry (CITIP), National Institute of Industrial Technology (INTI), INDEMAT (University of San Martín), CC 157, 1650 San Martín, Argentina
Department of Organic Chemistry, University of Buenos Aires, Pab.2, Ciudad Universitaria, 1428 Buenos Aires, Argentina
Plant Biophysics/Biochemistry Research Laboratory, College of Agriculture, Ehime University, Matsuyama 790-8566, Japan
Institute of Materials Science and Technology (INTEMA), University of Mar del Plata, CONICET, J. B. Justo 4302, 7600 Mar del Plata, Argentina
Palabras clave:Formic acid; Intramolecular cycles; Methacryloxypropyltrimethoxysilane; Molar mass distribution; Silsesquioxanes; Composition effects; Esters; Fourier transform infrared spectroscopy; Mass spectrometry; Molecular structure; Nuclear magnetic resonance spectroscopy; Polycondensation; Synthesis (chemical); Volume fraction; Organic acids
Año:2002
Volumen:35
Número:4
Página de inicio:1160
Página de fin:1174
DOI: http://dx.doi.org/10.1021/ma011305g
Título revista:Macromolecules
Título revista abreviado:Macromolecules
ISSN:00249297
CODEN:MAMOB
Registro:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_00249297_v35_n4_p1160_Eisenberg

Referencias:

  • Baney, R.H., Itoh, M., Sakakibara, A., Suzuki, T., (1995) Chem. Rev., 95, p. 1409
  • Sharp, K., (1994) J. Sol-Gel Sci. Technol., 2, p. 35
  • Wallace, W.E., Guttman, C.M., Antonucci, J.M., (1999) J. Am. Soc. Mass Spectrom., 10, p. 224
  • Wallace, W.E., Guttman, C.M., Antonucci, J.M., (2000) Polymer, 41, p. 2219
  • Fasce, D.P., Williams, R.J.J., Méchin, F., Pascault, J.P., Llauro, M.F., Pétiaud, R., (1999) Macromolecules, 32, p. 4757
  • Fasce, D.P., Williams, R.J.J., Erra-Balsells, R., Ishikawa, Y., Nonami, H., (2001) Macromolecules, 34, p. 3534
  • Matejka, L., Dukh, O., Hlavatá, D., Meissner, B., Brus, J., (2001) Macromolecules, 34, p. 6904
  • Eisenberg, P., Erra-Balsells, R., Ishikawa, Y., Lucas, J.C., Mauri, A.N., Nonami, H., Riccardi, C.C., Williams, R.J.J., (2000) Macromolecules, 33, p. 1940
  • Nonami, H., Wu, F., Thummel, R.P., Fukuyama, Y., Yamaoka, H., Erra-Balsells, R., (2001) Rapid Commun. Mass Spectrom., 15. , in press
  • Brinker, C.J., Assink, R.A., (1989) J. Non-Cryst. Solids, 111, p. 48
  • Doughty, D.H., Assink, R.A., Kay, B.D., (1990) Silicon-Based Polymer Science, p. 241. , Zeigler, J.M., Gordon Fearon, F.W., Eds.; Advances in Chemistry Series 224; American Chemical Society: Washington, DC
  • Bailey, J.K., Macosko, C.W., Mecartney, M.L., (1990) J. Non-Cryst. Solids, 125, p. 208
  • Rankin, S.E., Kasehagen, L.J., McCormick, A.V., Macosko, C.W., (2000) Macromolecules, 33, p. 7639
  • Feher, F.J., Newman, D.A., Walzer, J.F., (1989) J. Am. Chem. Soc., 111, p. 1741
  • Feher, F.J., Soulivong, D., Eklund, A.G., (1998) Chem. Commun., p. 399
  • Feher, F.J., Soulivong, D., Nguyen, F., (1998) Chem. Commun., p. 1279
  • Feher, F.J., Budzichowski, T.A., Blanski, R.L., Weller, K.J., Ziller, J.W., (1991) Organometallics, 10, p. 2526
  • Piana, K., Schubert, U., (1994) Chem. Mater., 6, p. 1504
  • McLafferty, F.W., Turecek, F., (1993) Interpretation of Mass Spectra, 4th Ed., p. 81. , University Science Books: Sausalito, CA

Citas:

---------- APA ----------
Eisenberg, P., Erra-Balsells, R., Ishikawa, Y., Lucas, J.C., Nonami, H. & Williams, R.J.J. (2002) . Silsesquioxanes derived from the bulk polycondensation of [3-(methacryloxy)propyl]trimethoxysilane with concentrated formic acid: Evolution of molar mass distributions and fraction of intramolecular cycles. Macromolecules, 35(4), 1160-1174.
http://dx.doi.org/10.1021/ma011305g
---------- CHICAGO ----------
Eisenberg, P., Erra-Balsells, R., Ishikawa, Y., Lucas, J.C., Nonami, H., Williams, R.J.J. "Silsesquioxanes derived from the bulk polycondensation of [3-(methacryloxy)propyl]trimethoxysilane with concentrated formic acid: Evolution of molar mass distributions and fraction of intramolecular cycles" . Macromolecules 35, no. 4 (2002) : 1160-1174.
http://dx.doi.org/10.1021/ma011305g
---------- MLA ----------
Eisenberg, P., Erra-Balsells, R., Ishikawa, Y., Lucas, J.C., Nonami, H., Williams, R.J.J. "Silsesquioxanes derived from the bulk polycondensation of [3-(methacryloxy)propyl]trimethoxysilane with concentrated formic acid: Evolution of molar mass distributions and fraction of intramolecular cycles" . Macromolecules, vol. 35, no. 4, 2002, pp. 1160-1174.
http://dx.doi.org/10.1021/ma011305g
---------- VANCOUVER ----------
Eisenberg, P., Erra-Balsells, R., Ishikawa, Y., Lucas, J.C., Nonami, H., Williams, R.J.J. Silsesquioxanes derived from the bulk polycondensation of [3-(methacryloxy)propyl]trimethoxysilane with concentrated formic acid: Evolution of molar mass distributions and fraction of intramolecular cycles. Macromolecules. 2002;35(4):1160-1174.
http://dx.doi.org/10.1021/ma011305g