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Dynamic and transient shear start‐up flow experiments along with TEM, WAXS, and SEM analyses are performed on PP/PET blends and nanocomposites. The TEM results along with a theoretical analysis based on a thermodynamic model reveal that the clay particles are mainly localized in the PET phase. The localization of nanoclay in PET as the matrix phase leads to a refinement of morphology. The localization of clay is also studied by analyzing changes in complex viscosity and storage modulus in oscillation mode as well as the changes in power law index obtained from steady‐state and transient shear start‐up flow experiments. The changes in the rheological behavior of the blends are attributed to formation of clay network‐like structures.magnified image

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Correlation of rheological response with microstructure and also the tensile mechanical properties of Nanoclay-filled Polyethylene (PE)/Ethylene vinyl acetate (EVA) blends were studied. From transmission electron microscopy observations, the same clay localization within PE-and EVA-rich blends was revealed. But the better clay dispersion in the EVA-rich blend was found by analyzing the changes in the linear viscoelastic rheological properties discussed by the fractional Zener model and the power law expression. Clay influences on the tensile properties of PE-and EVA-rich blends were in good agreement with its microstructure, implied by the rheological studies.

Poly(vinyl alcohol)/poly(ethylene glycol) hydrogels containing curcumin as a drug and the various amounts of a montmorillonite nanoclay are prepared using the freezing–thawing method. Nanoclay quantity influence on the physicomechanical properties and the drug release rate of the hydrogel as well as relationship between them is investigated. X‐Ray diffraction and Atomic force microscopy analysis reveal the nanoclays have an intercalation structure in the hydrogel, and the hydrogel crystallization decreases with increasing the nanoclay inclusion. From the SEM micrographs observation, it was revealed that due to the presence of the nanoclay in the hydrogel, its porosity decreased. The naonoclay has an amount‐depended dual effect on the hydrogel swelling. The swelling mechanism is a normal Fickian diffusion for all the hydrogel samples. Strong physical interactions between the nanoclays and the polymer chains in the nanocomposite hydrogels are evidenced by the rheological studies. These interactions lead to significant reinforcement of the hydrogel tensile strength, intensified by the nanoclay amount. Interestingly, the nanoclays show the capability of accelerating and, also, decelerating the drug release of the hydrogel. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47843.