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New polyamide/clay nanocomposites (PACN) were produced using semicrystalline polyamide (PA) containing thiazole ring and new organoclay (OC) through solution intercalation technique. For further study, PA/Cloisite‐15A nanocomposites (PAAN) were also prepared using PA and Cloisite‐15A. X‐ray diffraction (XRD), field emission‐scanning electron microscopy (FE‐SEM), and transmission electron microscopy (TEM) results showed a good dispersion for OC in the PA matrix. A meaningful decrease in intensity of absorption from ultraviolet–visible spectra as well as from fluorescence emissions of resulted PACN were observed. As thermogravimetric analysis (TGA) in nitrogen atmospheres showed, the T5 and T10 increased by about 57% and 36%, respectively for PACN containing 5 mass% of OC, as the char yield enhanced greatly, which was about 16.3% higher than the neat PA. Also the TGA results showed that PACN had higher thermal stability than PAAN. Differential scanning calorimetry (DSC) analysis exhibited higher glass‐transition temperature values (Tg) for PACN as compared to the neat PA. POLYM. COMPOS., 39:E1407–E1420, 2018. © 2017 Society of Plastics Engineers

1‐Hexene and 1‐octene oligomerization reactions were performed with Cp2ZrCl2 and Cp2HfCl2 in the presence of methylaluminoxane as cocatalyst at 25 and 80 °C to produce polyα‐olefin‐type oils. By examining the molecular weight results, obtained from gel permeation chromatography, the oligomeric structure of the products was confirmed. Hafnocene produced oligomers with higher molecular weights in comparison with zirconocene under the same reaction condition. In addition, with increasing temperature, the molecular weight decreased. Differential scanning calorimetry analysis of the poly1‐hexene‐ and poly1‐octene‐type oligomers confirmed their amorphous nature. 1H‐nuclear magnetic resonance (NMR) analysis was performed to study the mechanism of termination reactions. The results obtained from the 1H‐NMR analysis confirmed the vinylidine form (vd) as the only unsaturated structure in all synthesized oligomers. Therefore, in the 1‐hexene and 1‐octene oligomerization reactions with these two catalytic systems, the chain termination is totally accomplished by β‐hydride elimination at both reaction temperatures.

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