Purification of Thermotropic Liquid-Crystalline Siloxane Oligomer with Supercritical Carbon Dioxide.

摘要

The effects of the purification of thermotropic liquid- crystalline siloxane oligomer with supercritical carbon dioxide were investigated. It was found that low-molar-mass contaminants, presumably the two alkene precursors, can be effectively removed at 80 C and carbon dioxide pressures up to 31,0 MPa. In support of this observation is the fact that glass transition temperature goes up as a result of purification. In addition, the selective reflection wavelength was found to increase at increasing purity level, as achieved by extraction at increasing carbon dioxide pressure. Liquid crystalline, Purification, Supercritical fluids, Digomers. Reprints. (jes)