Summary: The ordering behavior of the nanocomposites of organically modified montmorillonite (OMMT) with a cylindrical triblock copolymer of polystyrene‐block‐poly(ethylene‐co‐butylene)‐block‐polystyrene (SEBS) has been investigated by temperature‐resolved small‐angle X‐ray scattering (SAXS) and rheometry. X‐Ray diffraction (XRD) confirms that the polymer chains are successfully intercalated with the interlayer gallery of the silicates. The data obtained from the SAXS and rheological measurements show that the addition of OMMT leads to a change in the microphase separation behavior of SEBS in the nanocomposites. The molecular interaction between OMMT and the polystyrene (PS) chains of SEBS decreases the structural perfection of the self‐assembling, phase‐separated domain structure of the nanocomposites. Rheological data exhibit that the order‐order (TOOT) and order‐disorder transitions (TODT) of the SEBS/OMMT nanocomposites decrease with the addition of OMMT. The highest elongation at break is obtained at approximately 2% OMMT and its further addition to the mixture leads to decreases in tensile strength and elongation.The change in the storage modulus (G′) of a) SEBS, b) S98M2, c) S95M5, and d) S90M10, as a function of temperature in the range of 150 ≤ T (°C) ≤ 260.magnified imageThe change in the storage modulus (G′) of a) SEBS, b) S98M2, c) S95M5, and d) S90M10, as a function of temperature in the range of 150 ≤ T (°C) ≤ 260.

Synthetic biodegradable aliphatic polyester (BAP) and its blends with polyepichlorohydrin (PECH) were processed with organophilic montmorillonite (OMMT) to make polymer/organoclay nanocomposites via a solvent casting method. Interlayer spacings of each system, measured by X-ray diffraction analysis, suggested that BAP had better affinity to clay than PECH in a competitive intercalation mechanism. The internal structures were visualized using transmission electron microscopy and were discussed in conjunction with the result of other experimental studies, such as thermogravimetric analysis and rheometry. In rheological measurements, the degree of shear-thinning increased drastically with OMMT loading, and both the storage modulus and loss modulus were found to increase with OMMT loading at all frequencies. Throughout this study, we compared the behaviours of polymer/clay nanocomposites in homo and blend systems, and examined the role of various parameters on the material characteristics of polymer/clay nanocomposites.