Impregnation of Ru(cod)(tmhd)(2) into PDMS film in supercritical carbon dioxide

Abstract

Metallopolymer nanocomposites has attracted much attention recently. The impregnation of organometallic compound from the supercritical solution into the polymer matrix has several advantages. The impregnation process isotherm of bis(2,2,6,6-tetramethy1-3,5-heptanedionato) (1,5-cyclooctadiene) ruthenium (II) (Ru(cod)(tmhd)(2)) into polydimethylsiloxane (PDMS) film in supercritical carbon dioxide (scCO(2)) was investigated. The experiments for determining the isotherm were carried out at 40 degrees C and 10.34 MPa. It was found that the impregnation isotherm is linear up to the saturation concentration of the precursor in scCO(2) fluid phase. The slope of the linear curve defined equilibrium partition coefficient K provides a measure of the partitioning of Ru(cod)(tmhd)(2) between the PDMS film and scCO(2) fluid phase and it is constant under the same conditions. It showed that K is mainly govered by the density of scCO(2) and does not change much with temperature at a constant density of scCO(2).