Key words: impregnation, polymethylmethacrylate, carbamazepine, supercritical CO2
In this work we performed an impregnation of polymethylmethacrylate with carbamazepine
in SC-CO2 medium. Impregnation was carried out at two temperatures of 75 °C and
105 °C and SC-CO2 density equal 1.3 of its critical value. In the first stage, in order to
define the kinetic parameters of CO2 sorption by polymer matrix, we applied high pressure
NMR spectroscopy. Two impregnated polymethylmethacrylate samples were obtained
upon impregnation process and further they were analyzed by Raman spectroscopy and
powder X-Ray diffraction.
Basing on the results of Raman spectroscopy we found that both impregnated samples
contain carbamazepine, at that its concentration in polymethylmethacrylate impregnated
at 105 °C is in ∼2.7 times higher than in polymethylmethacrylate processed at 75 °C. It
was also discovered that carbamazepine does not crystallize in the confinement of polymer
matrix. Its solution in polymethylmethacrylate is formed instead. Moreover, processing
temperature also affects on conformational state of carbamazepine molecules entrapped
into polymer matrix.
doi:10.1134/S1990793121070101