In this article, we report the supramolecular assemblies of a semirigid polyelectrolyte, poly(2,2′-disulfonyl-4,4′-benzidine terephthalamide) (PBDT) in water. Cryo-TEM observation and SAXS measurement reveal that PBDT forms bundle-like structure even in very dilute concentration, C P, of 0.02 wt %. These bundle-like assemblies serve as new primary building blocks and self-assemble further as C P increases, to form large associations with or without long-range orientation. When 2 wt % < C P < 6 wt %, liquid–liquid phase separation occurs. Some of the supramolecular associations form bipolar liquid crystalline (LC) droplets via a typical nucleation and growth process. The droplets grow up by the coalescence of small ones and sediment under the gravity and coalesce to form a bottom nematic phase. When C P ≥ 6 wt %, the solutions are in a uniform nematic phase. The existence of these preliminary supramolecular assemblies of PBDT in aqueous solutions should be crucial for the formation of nematic LC phase at a significantly low C P, as well as the formation of macroscopic ordered structures in hydrogels via electrostatic interaction between PBDT and oppositely charge multivalent metallic ion or polycation.

In this paper, we developed several kinds of ordered structures in hydrogels with different geometries and sizes by harnessing heterogeneous swelling induced mechanical instability, i.e., surface creasing, which leads to molecular orientations along the tensile direction. These hydrogels were synthesized by polymerization of a cationic monomer, N-[3-( N,N -dimethylamino)­propyl] acrylamide methyl chloride quaternary (DMAPAA-Q) and a chemical cross-linker, in the presence of a small amount of the semirigid polyanion, poly­(2,2′-disulfonyl-4,4′-benzidine terephthalamide) (PBDT), as dopant. During the swelling process of as-prepared gels, surface creasing occurs and induces formation of a lattice-like periodic ordered structure, which is maintained in the swollen gels due to the formation of strong polyion complex. Besides this structure formed at the central part of gel sheets, PBDTs align parallel to the gel boundary at the edge of gels with a cuboid, disk, or ring shape. The size of the two regions with different structures and the size of each unit of lattice-like pattern are related to the geometry and size of the gels. The formation of different ordered structures was found due to the different mechanical instabilities at different parts of the gel during the heterogeneous swelling. This work presenting the creation of ordered structures in hydrogels by tuning the mechanical instability will pave the way to develop other functional structured materials and merit revealing the formation mechanism of ordered structures in soft biotissues during the nonequilibrium growth.

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Impulse buying behavior among consumers was previously examined within the brick-and-mortar stores. The internet revolution is the shift from a traditional retail environment to electronic commerce where products and services are offered online and consumers benefit from buying impulse towards e-tailing sites. By applying the S-O-R model, this study seeks to evidently identify the influencing factors of impulse buying behavior towards e-tailing sites. The survey data were analyzed using partial least squares structural equation modeling (PLS-SEM). The result indicates that website stimulus has no significant positive relationship with online impulsive buying behavior, but an indirect relationship is found to be associated with impulse buying behavior. Results also highlighted that website stimulus, marketing stimulus, and product variety positively influence perceived enjoyment, where perceived enjoyment was a strong predictor of online impulse buying behavior. The study contributes to the existing literature by Contemporary Management Research 98 employing external stimuli of the research framework. It was thus recommended to the online e-tailers to maximize their relationship with consumers by providing valuable products and services through online platforms.