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The influence of different steric and electronic properties of 2,4-; 2,5-; and 3,5- dimethylphenols (2,4-; 2,5-; and 3,5- DMP, respectively) on Ni-montmorillonite (Ni-MMT) (I) were studied. The results of X-ray diffraction show that the observed changes of the basal spacing were due to the intercalation of phenol derivatives into the interlayer space of montmorillonite. The existence of one peak at ~1,633 cm in the IR spectra of sample Ni-MMT + 2,4-DMP (II) and Ni-MMT + 2,5-DMP (III) and shift of this peaks to higher frequency indicate that 2,4-DMP and 2,5-DMP exist in the interlayer space of Ni-MMT in the protonated form. The two bands at ~1,622 and 1,597 cm in the sample Ni-MMT + 3,5-DMP (IV) indicate that 3,5-DMP may be also directly coordinated to Ni cations. The different interactions of phenol derivatives in the silicate interlayers will be connected with different position of methyl groups on the phenol ring. [ABSTRACT FROM AUTHOR]

The influence of the 2-, 3-, and 4-OH phenols on the type of interaction with Co-exchanged montmorillonite and thermal properties of these materials were studied. The results of XRD, IR, and thermal (TG, DTG) analysis show that organic species are intercalated into the interlayer space of montmorillonite. Thermal decomposition in the temperature interval 20-700 °C of studied samples with 2- and 3-hydroxyphenol proceeds in three steps (the release of adsorbed HO molecules, combustion/desorption of protonated hydroxy phenols and dehydroxylation), while the sample with 4-hydroxyphenol decompose in four steps (the new peak at ~222 °C corresponds to directly coordinated organic species). The effect of different position of the hydroxyl groups on the phenol ring on the thermal decomposition is evident. [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]

Thermal analysis (TG, DTG), powder diffraction analysis (XRD) and infrared (IR) spectra were used to study of composition and release of benzimidazole from Ni(II)-exchanged montmorillonite under heating. Diffraction analysis indicated that benzimidazole molecules are intercalated into the interlayer space of montmorillonite. IR spectra and the analytical characteristics have shown that different type of interactions of benzimidazole is connected with different reaction conditions (acid or neutral solution). The release of benzimidazole from Ni(II)-montmorillonite under heating from studied samples proceeds in three distinct steps. The first step can be assigned to the release of water molecules while the last (third) one corresponds to the lattice dehydroxylation. The second step can be assigned to release of chemically bonded benzimidazole. [ABSTRACT FROM AUTHOR]