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Materials with highly ordered molecular arrangements have the capacity to display unique properties derived from their nanoscale structure. Here, the synthesis and characterization of azobenzene (AZO)-functionalized siloxane oligomers of discrete length that form photoswitchable supramolecular materials are described. Specifically, synergy between phase segregation and azobenzene crystallization leads to the self-assembly of an exfoliated 2D crystal that becomes isotropic upon photoisomerization with UV light. Consequently, the material undergoes a rapid athermal solid-to-liquid transition which can be reversed using blue light due to the unexpectedly fast 2D crystallization that is facilitated by phase segregation. In contrast, enabling telechelic supramolecular polymerization through hydrogen bonding inhibits azobenzene crystallization, and nanostructured pastes with well-ordered morphologies are obtained based on phase segregation alone, thus demonstrating block copolymer-like behavior. Therefore, by tailoring the balance of self-assembly forces in the azobenzene-functionalized siloxane oligomers, fast and reversible phase-changing materials can be engineered with various mechanical properties for applications in photolithography or switchable adhesion to lubricant properties. [ABSTRACT FROM AUTHOR]

The formation of multicomponent and bioactive supramolecular polymers is a promising strategy for the formation of biomaterials that match the dynamic and responsive nature of biological systems. In order to fully realize the potential of this strategy, knowledge of the location and behavior of bioactive components within the system is crucial. By employing synthetic strategies to create multifunctional monomers, coupled with FRET and STORM techniques, we have investigated the formation and behavior of a bioactive and multicomponent supramolecular polymer. By creating a peptide-dye-monomer conjugate, we were able to measure high degrees of monomer incorporation and to visualize the equal distribution of monomers within the supramolecular polymer. Furthermore, by tracking the movement of monomers, we uncovered small differences in the dynamics of the bioactive monomers., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)