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Polymers formed by the self-assembly of a bis(urea)-basedpolymer,2,4-bis(2-ethylhexylureido)toluene (EHUT), in organic solvents suchas octane are promising systems with remarkable rheological properties.This is the first self-assembled polymer recently reported as a hydrodynamicdrag reducer for hydrocarbons. The rheology of diluted and semidilutedEHUT solutions can be tuned by specific interactions between the chains,modulated by the nature of the solvent and the presence of additives.In this article, rheological, thermal and SANS measurements were performedin order to investigate the competition between EHUT self-assemblyand its interaction with specific molecules (benzene, benzyl alcohol,and ethanol) that can interact with EHUT unimers via hydrogen bondsand π–π interactions. No substantial rheological,thermal, or structural effect is observed when benzene is added tothe systems. However, ethanol and benzyl alcohol interact with EHUTunimers through hydrogen bonds, drastically decreasing the viscoelasticityof the solutions. In addition, benzyl alcohol can interact with EHUTpolymers by π-stacking interactions, playing an important rolein tuning the rheological properties of the systems. [ABSTRACT FROM AUTHOR]

New amphiphilic random copolymers containing hydrophobic dodecyl (C12) chain and hydrophilic l-glutamic acid were synthesized, and their self-assembly in solution as well as on the solid surfaces was investigated. The self-assembly behavior of these polymers are largely dependent on their hydrophilic and hydrophobic balances. The copolymer with a more hydrophobic alkyl chain (∼90%) self-assembled into giant vesicles with a diameter of several micrometers in a mixed solvent of ethanol and water. When the hydrophobic ratio decreased to ca. 76%, the polymer self-assembled into conventional vesicles with several hundred nanometers. The giant vesicles could be fused in certain conditions, while the conventional vesicles were stable. When the content of the hydrophilic part was further increased, no organized structures were formed. On the other hand, when the copolymer solutions were directly cast on solid substrates such as silicon plates, films with organized nanostructures could also be obtained, the morphology of which depended on solvent selection. When ethanol or methanol was used, spheres were obtained. When dichloromethane was used as the solvent, honeycomb-like morphologies were obtained. These results showed that through appropriate molecular design, random copolymer could self-assemble into various organized structures, which could be regulated through the hydrophobic/hydrophilic balance and the solvents. [ABSTRACT FROM AUTHOR]