exciton-hopping (with site-to-site hopping times of 2 ps), enabling the efficient
collection and transport of excitation energy [59].
4.2 Recyclable Noncovalent Membranes
4.2.1 Nanoparticle Separations
Working with the aqueous solutions of 8, we made an intriguing observation –
when we filtered the solutions over standard syringe filters with 400 nm pores, the
material was quantitatively retained (deposited) on the filters (Fig. 13a, b), with
virtually no observable amount of 8 coming through (even upon applying moderate
pressure), in contrast to the majority of assemblies we had been investigating.
Despite the fact that the system is composed of relatively small molecules, the
hydrophobic interactions appeared to be very strong, prompting us to state that the
3D networks of 8 display unique robustness. This would be an empty claim without
Fig. 11 (a) Reversible gel–sol switching using redox chemistry accompanied by (b) birefringence
switching (scale bar: 200 μm) [59]
Fig. 12 (a) Temperature responsiveness and (b) multiple stimuli responsiveness of the gel [59]
Aqueous Supramolecular Polymers Based on Aromatic Amphiphiles: Rational. . .
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