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double metal cyano (DMC) catalyst is very effective for ring opening polymerization of propylene oxide (PO). The characteristics of the DMC complex were studied by Fourier transform infrared spectroscopy (FTIR) and thermogravimetry (TG). DMC complex generally result in a significant reduction of monols in the polyol production process. DMC catalyst is characterized by an approximately 1000 times higher activity compared to the conventional KOH catalyst. Disadvantages of the conventional KOH process are long reaction times, costly work-up procedures to remove the base catalyst and the formation of undesired unsaturated by-products (so called 'monols') especially in the preparation of long chain polyether polyols. [ABSTRACT FROM AUTHOR]

This paper is devoted to the investigation of the properties of the natural rubber composites prepared using the cation exchanged-montmorillonite fillers. The characteristics of the montmorillonite fillers were studied by Fourier transform infrared spectroscopy (FTIR) and thermogravimetry (TG). These characterized fillers were used to preparation of the natural rubber composites, which were submitted to measurements of dynamic-mechanical thermal analysis (DMTA) and vulcanizing characteristics ( M, M, t, t, R) as well as physico-mechanical properties (tensile strength, modulus at 300 elongation- M, tensibility). [ABSTRACT FROM AUTHOR]

The influence of different steric properties of ethylenediamine (EDA), trimethylenediamine (TrMeEDA) and tetraethylenediamine (TeMeEDA) on the type of interactions with Co(II)-exchanged montmorillonite and thermal decomposition of these materials were studied. The results of X-ray diffraction (XRD), thermogravimetry (TG), derivative thermogravimetry (DTG) and spectral analysis shows that the studied ethylenediamines are intercalated into the interlayer space of montmorillonite. Thermal decomposition at 20-500 °C of studied samples with EDA proceeds in three steps (the release of chemosorbed amines, coordinated EDA and dehydroxylation) while the sample with TrMeEDA and TeMeEDA in five steps (also release the protonated forms). The effect of different steric properties of individual diamines is evident. [ABSTRACT FROM AUTHOR]