Carbonated soybean oil (CSO) containing five-membered cyclic carbonate groups has been obtained in the reaction of epoxidized soybean oil with carbon dioxide in the presence of KI activated by 18-crown-6 under 6 MPa CO 2 pressure at 1308C. The CSO was used for modification of bisphenol-A based epoxy resin. The composition epoxidecyclic carbonate was cured using polyamine hardeners by one-step and two-step procedures. All cured compositions were characterized for their thermal and mechanical properties and compared with the parent epoxy network. The optimal properties were obtained for compositions containing CSO and cured by one-step method when phase separation takes place. The mechanical properties were discussed in terms of morphology observed by SEM.

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The aim of this work was to investigate the influence of different types of carbon filler on the thermal stability and flammability of rigid polyurethane foams. As a filler, multi-walled carbon nanotubes and graphite fakes were used. Scanning electron microscopy was used to observe the structure of foam and dispersion of nanofiller in polymer matrix. Thermal stability of these composites was determined by thermogravimetry analysis. Test was carried out under both nitrogen and air atmosphere. The degradation products were evaluated by thermogravimetry (TG) combined with infrared spectroscopy (TG-IR) measurements. The activation energy was measured by the Flynn-Wall-Ozawa method from the TG curves. Flammability tests like limiting oxygen index and smoke density were also measured. No significant changes in the thermal stability of the composites were observed. The activation energy of sample containing carbon filler increased. Based on TG-IR, one can notice that there were no differences in the emitted volatile products during thermal degradation. Carbon filler enhanced fire retardancy of polyurethane foam; however, graphite gives better results.

The reaction of boehmite with diethyl phosphoric acid generated in situ in a boiling water solution of triethyl phosphate has been studied in detail. Two kinds of solid products have been isolated and characterized by elemental and XPS analysis, in addition to XRD, TGA, FT-IR, SEM, and MAS NMR techniques. One of them precipitates from the reaction mixture in the form of fibers containing needlelike hexagonal crystals with the unit-cell parameters a = 21.105(4) Å and c = 9.112(2) Å (V = 3515(1) Å3). The crystalline structure comprises hexagonally packed catena Al[OP(O)(OC2H5)2]3 chains. The other ones form a colloidal dispersion of spherical nanoparticles that consist of a boehmite core covered by aluminodiethylphosphate chains. The NMR studies of the reaction mixture indicate that water soluble aluminophosphate species are also formed in the systems studied. These species are suggested to act as nutrients for the growth of aluminophosphate structures. Colloidal particles and fibers have been included into the polyurethane matrix by in situ polyaddition. The SEM images of the composites surface cross-section shows that spherical nanoparticles are homogeneously distributed in the polymers, whereas fibers tend to agglomerate. Some mechanical reinforcement of the surface of polyurethanes has been accomplished as indicated by the abrasive wear test and AFM images.

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