High-performance Liquid Chromatographic Stationary Phases Based On Poly(methyloctylsiloxane) Immobilized On Silica. I. Physical And Chemical Characterizations.

Five different reversed-phase materials for high-performance liquid chromatography were obtained by deposition of poly(methyloctylsiloxane) in HPLC silica particles, followed by immobilization using different processes: thermal treatment (120 or 220 degrees C for 4 h), irradiation with microwaves (495 W for 15 min), gamma radiation (dose of 80 kGy) and self-immobilization. These phases were characterized by gel permeation chromatography, percent carbon, 13C and 29Si solid-state nuclear magnetic resonance spectroscopy, infrared spectroscopy, thermogravimetric analysis and scanning electron microscopy. The results show that the different immobilization processes produce different physical characteristics in the prepared phases.94897-10