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Tuning of the morphology and sizeof supramolecular self-assembliesis of theoretical and practical significance. To date, supramoleculardriving forces in different solvents remain unclear. In this study,we first synthesized an amphiphilic β-cyclodextrin (β-CD)dimer that consists of one hydrophobic ibuprofen (Ibu) and two hydrophilicβ-CD moieties (i.e., Ibu-CD2). Ibu-CD2possesses double supramolecular driving forces, namely, the host–guestrecognition and hydrophilic–hydrophobic interaction. The host–guestinteraction of Ibu-CD2induced the formation of branchedsupramolecular polymers (SPs) in pure water, whereas the hydrophilic–hydrophobicinteraction generated spherical or irregular micelles in water/organicmixtures. The SP size increased with the increase in Ibu-CD2concentration in pure water. By contrast, the size of micelles decreasedwith the increase in volume ratio of water in mixtures. [ABSTRACT FROM AUTHOR]

The controlled secondary self-assembly of amphiphilic molecules in solution is theoretically and practically significant in amphiphilic molecular applications. An amphiphilic β-cyclodextrin (β-CD) dimer, namely LA-(CD)2, has been synthesized, wherein one lithocholic acid (LA) unit is hydrophobic and two β-CD units are hydrophilic. In an aqueous solution at room temperature, LA-(CD)2 self-assembles into spherical micelles without ultrasonication. The primary micelles dissociates and then secondarily form self-assemblies with branched structures under ultrasonication. The branched aggregates revert to primary micelles at high temperature. The ultrasound-driven secondary self-assembly is confirmed by transmission electron microscopy, dynamic light scattering, 1H NMR spectroscopy, and Cu2+-responsive experiments. Furthermore, 2D NOESY NMR and UV/Vis spectroscopy results indicate that the formation of the primary micelles is driven by hydrophilic-hydrophobic interactions, whereas host-guest interactions promote the formation of the secondary assemblies. Additionally, ultrasonication is shown to be able to effectively destroy the primary hydrophilic-hydrophobic balances while enhancing the host-guest interaction between the LA and β-CD moieties at room temperature. [ABSTRACT FROM AUTHOR]

Abstract: Large complex micelles based on H-shaped terpolymers (poly(ethylene glycol))(poly(N,N-dimethylaminoethyl methacrylate))-polytetrahydrofuran-(poly(N,N-dimethylaminoethyl methacrylate)) (poly(ethylene glycol)) ((PEG)(PDMA)-PTHF-(PDMA)(PEG)), with proper block ratio, are obtained through ultrasonic vibration. However, similar micellar morphology is not found using other traditional methods, such as evaporation and dialysis. According to the predicted thermodynamic analysis, large complex micelles consisting of several multimicelles are a result of the cooperative effects of ultrasonic vibration, hydrophobic–hydrophilic block ratio, and H-shaped branched architecture. These findings may lead to new strategies in designing supramacromolecular materials that exhibit special properties. [Copyright &y& Elsevier]