Self-immobilization and/or thermal treatment for preparing silica-poly(methyloctylsiloxane) stationary phases.
J Chromatogr A
; 1030(1-2): 217-23, 2004 Mar 19.
Article
en En
| MEDLINE
| ID: mdl-15043272
Batches of poly(methyloctylsiloxane) (PMOS)-loaded silica were prepared by the deposition of PMOS, into the pores of HPLC silica. Portions of PMOS-loaded silica were allowed to remain at ambient temperature, without further treatment for 2, 9, 20, 31, 51, 105 and 184 days after preparation to undergo self-immobilization (irreversible adsorption of a layer of polymer on silica at ambient temperature in the absence of initiators). Other portions were subjected to a thermal treatment (100 degrees C for 4h) after 1, 2, 5, 7, 9, 15, 20, 25, 70, 111 and 184 days. Self-immobilized and thermally treated samples were characterized by % C, 29Si cross-polarization magic angle spinning (CP/MAS) NMR spectroscopy and reversed-phase column performance. The results show that thermal immobilization accelerates the distribution and rearrangement of the polymer on the silica surface. However, from the time that a monolayer has been formed by self-immobilization (approximately 100 days for PMOS on Kromasil silica), the thermal treatment does not alter this configuration and, thus, does not change the resulting chromatographic parameters.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Polímeros
/
Siloxanos
/
Dióxido de Silicio
Idioma:
En
Revista:
J Chromatogr A
Año:
2004
Tipo del documento:
Article
País de afiliación:
Brasil
Pais de publicación:
Países Bajos