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A one-pot supercritical fluid (SCF) method was applied to prepare a series of silica aerogels. They were formed from alkoxysilanes by the sol–gel process directly in supercritical carbon dioxide. By this method no additional solvents are needed and the process of drying of wet gel afterwards is simplified. This method was modified by the addition of reactive polydimethylsiloxane (PDMS) chains, which yielded in organically modified silicates, the so-called “ORMOSILS” or in our case “AEROMOSILS” when prepared in the form of aerogels. The investigation of the prepared materials by atomic force microscopy (AFM) showed that they consisted mainly of particles with a diameter of 50–100 nm. 2–3 nm pores in these particles were indicated on the images. Further modification of the SCF method to yield AEROMOSILS with immobilized palladium particles was successful. This material was tested as a catalyst both for batch and continuous supercritical hydrogenation of 2,5-dihydro-2,5-dimethoxy-furane.

Swelling of polystyrene (PS) in supercritical carbon dioxide was studied in situ. Experiments were carried out in a high-pressure cell furnished with an optical channel. This allowed to measure the dynamics of diffusion front propagation in the polymer samples during the swelling process by the use of an optical microscope supplied with a digital video camera. The measurements of this dynamics provided information about diffusion coefficients of CO 2 molecules in PS. Diffusion coefficients and equilibrium sorption degrees of the PS samples were also calculated by the use of a gravimetric method. The data were compared with the results of in situ technique. Impregnation of PS films wish ethyl-2-cyano-3(4′-dimethylaminophenyl)acrylate as a model substance for UV-filters and electrographic materials was carried out.

One-step polycyclization reaction in supercritical carbon dioxide has been carried out for the first time and a thereby set of polyimides has been synthesized. Diphenyl-2,2-hexafluoropropane-3,3′,4,4′-tetracarboxylic acid dianhydride (dianhydride 6F), 4,4′-diaminodiphenyl-2,2-hexafluoropropane (diamine 6F) and 9,9-bis(4-aminophenyl)fluorene were used as monomers. Maximum inherent viscosity of the synthesized polymers is 0.56 dl/g. It is supposed that carbon dioxide act as an acidic catalyst for the reaction in the presence of water admixture.