By introducing strong directed hydrogen bonds to an amphiphilic polymer, we demonstrate that phase transitions from spherical to cylindrical morphologies in aqueous solutions can significantly be shifted to favor the assembly of supramolecular polymer bottlebrushes. In water, a forced self-assembly of polymers into cylindrical structures remains a challenge as the often required hydrophobic shielding induces forces, which tend to minimize the surface area. The herein presented novel benzene trisureas can overcome these limitations due to strong hydrogen bonds and alter the morphology to cylinders despite an unfavorable packing parameter, which dominated the previously reported trisamide analogues. The systematic variation of composition and architecture revealed that a transition to spherical morphologies still occurs, but the phase-transition boundaries appear to be shifted to tolerate larger hydrophilic polymer chains. The strength of the directing interactions appears to be decisive for the shift, though we additionally observed that any restrictions of lateral aggregation can diminish the effect of the directing hydrogen bonds. Overall, the straightforward synthesis and versatile design render the presented systems an interesting blueprint for the development of more advanced supramolecular polymer bottlebrushes and multifunctional nanostructures.

The assembly of polymer building blocks into supramolecular bottlebrushes by non-covalent forces represents an exciting new field of research. This review provides an overview on suitable motifs and requirements for the formation of such structures.

Reactive polymersomes represent av ersatile artificial cargo carrier system that can facilitate an immediate release in response to aspecific stimulus.The herein presented oxidation-sensitive polymersomes feature at ime-delayed release mechanism in an oxidative environment, whichc an be precisely adjusted by either tuning the membrane thickness or partial pre-oxidation. These polymeric vesicles are conveniently prepared by PISA allowing the straightforwarda nd effective in situ encapsulation of cargo molecules,asshown for dyes and enzymes.Kinetic studies revealed acritical degree of oxidation causing the destabilization of the membrane,w hile no release of the cargo is observed beforehand. The encapsulation of glucose oxidase directly transforms these polymersomes into glucose-sensitive vesicles,a ss mall molecules including sugars can passively penetrate their membrane. Considering the ease of preparation, these polymersomes represent av ersatile platform for the confinement and burst release of cargo molecules after ap recisely adjustable time span in the presence of specific triggers,s uch as H 2 O 2 or glucose.

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