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Designer supramolecular polymers are a growing field of polymer materials. The designability and flexibility in their structures and functionality have attracted a great deal of attention in polymer science, as well as in supramolecular chemistry. These polymeric structures are formed from one or more molecular components via reversible bonds; therefore, monomeric and polymeric states are in equilibrium on the relevant experimental timescale. The dynamic nature of supramolecular polymers in terms of chain lifetime and conformational flexibility are determined by external conditions. This adaptivity can result in stimuli-responsive structures and properties. This article describes the use of our host–guest structures based on a calix[5]arene, a bisporphyrin, and a self-assembled capsule in the synthesis of supramolecular polymers.

The amorphous phase and crystalline morphology of the poly(vinyl methyl ether) (PVME)/poly(1,6-hexamethylene adipate) (PHA) blend were compared with those of the classical PVME/poly(ɛ-caprolactone) (PCL) system, isomeric to the former. Both blend systems’ amorphous phases are similarly miscible with χ₁₂=−0.2. In contrast, the crystalline phases of these two blends differ significantly. When crystallized at high T_c (46 °C or above), the PVME/PCL (20/80) blend assumes fluffy feather-like dendrites (Graph-a), which are dramatically different from straight-stalk dendrites in the PVME/PHA (20/80) blend (Graph-b).

The 2D WAXD/SAXS data collected using a synchrotron X-ray microbeam technique revealed the details of the lamellar twisting phenomenon of high-density polyethylene spherulites. The molecular mechanics calculation, performed for large aggregation models of alkane chains having bulky head groups or folded polyethylene chains, has successfully reproduced the lamellar twisting pitch of a few μm, as extracted from the X–ray data analysis.

Atomic force microscopy (AFM) phase images for the ridge and valley regions of the water-etched poly(ethylene oxide)/poly(L-lactic acid) (50/50) blend crystallized at crystallization temperature (T_c)=110 °C. The AFM graph (5 μm×5 μm) of the ridge region b shows a texture different from that of the valley region c. The surface patterns of the lamellae in the valley and ridge in these two regions appeared as flat-on and edge-on lamellae, respectively. The anisotropicity of the platelet crystals in these two regions was also apparently different. The orientation of the crystal lamellae in the valley (region c) was circumferential, whereas that of the lamellae in the ridge (region b) was radial. The difference in orientation in the ridge and valley regions may account for the cracks in the ridge regions but not in the valley region.