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Different catalyst samples of nickel(II) and copper(II) phthalocyanines supported over bentonite clay (Indian type) were prepared with complex loadings ranging between 0.2 and 2.2 wt.‐%. Catalyst activities were investigated in the bulk polymerization of methyl methacrylate (MMA) at 80°C in the absence and in the presence of sodium bisulfite as a cocatalyst. In all cases, the catalyst efficiency was evaluated in terms of conversion yield (%), polydispersity index (M̄w/M̄n) was determined via GPC analysis in toluene. The stereotacticity was determined from 1H NMR spectra. Optimum polymerization conditions were determined for both catalyst systems. Samples with metal phthalocyanines loadings of 1.8% were the most active ones. The polymers produced have controlled molecular weights, which are nearly proportional to conversion, show narrow molecular weight distributions and syndiotactic‐rich steric structures. Nickel phthalocyanine seemed to have more stereoregulating effect while copper phthalocyanine had a more enhancing effect for the living polymerization process. The microstructure of solid catalysts was investigated by means of scanning electron microscopy and were correlated with activity data.

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Rubber nanocomposites based on styrene-butadiene rubber (SBR) and organophilic layered silicate were prepared. Clay structures based on dodecyl benzene sulfonic acid (DBSA), nonyl phenol ethoxylate (NPE), and DBSA/NPE (50/50%) were prepared and characterized. The results indicate the intercalation of the used surfactants within the clay layers. Varying amount of organoclay, 2, 4, 6, 8, and 10 (phr), was added to the SBR matrix. X-ray diffraction revealed exfoliated structure for the modified clay-SBR composites. No new component in the rubber was found by fourier transform infrared measurements (FTIR). Scanning electron microscopy showed a uniform distribution of the modified clay with mixed DBSA/NPE (6 phr) in the matrix. The rheometric characteristics and physicomechanical properties of the SBR compounds were analyzed. The effect of DBSA/NPE clay loading on aging resistance of SBR nanocomposites at 90 6 1 C for 4 and 7 days was also investigated. Rubber nanocomposites displayed an increase in the minimum and maximum torques, acceleration of the vulcanization process, and improved mechanical properties, with organoclay content up to 6 phr. This effect was more noticeable in the presence of the treated clay with DBSA/NPE. Also incorporation of DBSA/NPE-clay (6 phr) resulted in significant improvement of the degradation profile of the nanocomposites at 90 6