Reversible morphological switching of nanostructures in solution

Abstract

The design and synthesis of a tuneable and reversible morphology switching copolymer system is reported. The kinetics of the transition under a range of conditions has been explored, as has the stabilization of the resultant structures.

Morphology Transition of Dual‐Responsive ABC Terpolymer in Water: Effect of Hydrophobic Block

“…In this study, the T g of P n BMA and P n HMA are 20 and −5 °C, respectively . Therefore, the micelle core is rubbery at 25 °C in the case of EBD and EHD, facilitating the pH‐induced morphology transition . However, the T g of PMMA and PEMA are 100 and 65 °C, respectively, much higher than 25 °C, suggesting that the micelle core of EMD and EED was too hard for the fusion and rearrangement of micelle.…”

“…By replacing PNIPAM with a statistic copolymer of poly(ethylene oxidestat‐butylene oxide), the micelle‐to‐vesicle transition was achieved within one week . Adopting a similar design method, reversible switch from micelle to high‐ordered structures was reported by other groups . However, most of the previous studies were focused on alteration in the packing parameter ( p ) of the responsive copolymers upon external stimuli.…”

“…In contrast, only a few reports investigated the kinetic parameters although the rearrangement of micelle was crucial for morphology switch. For example, by replacing poly( t ‐butyl acrylate) with poly(methyl acrylate), a faster transition from micelle to vesicle was achieved by O’Reilly group . Using PNIPAM with short alkyl tails to decrease kinetic barrier of morphology transition, Jiang and coworkers shortened the time extend of micelle‐to‐vesicle transition to 30 min .…”

Stimuli-responsive polymersomes and nanoreactors

“…O'Reilly's group have reported thermally induced micelle to vesicle morphology transitions of amphiphilic block copolymers. 66,67 They synthesised PNIPAM containing diblock copolymers that were able to self-assemble into nano-objects in aqueous solution. These nano-objects could undergo a relatively fast and fully reversible transition from micelle to vesicle morphologies (Fig.…”

Eine genügt: Beeinflussung von Polymereigenschaften mittels einer einzelnen Chromophoreinheit

“…[4] Von besonderem Interesse sind reversible morphologische Veränderungen von Nanostrukturen in Lösung. [5] Ein derartiges Verhalten wird oft durch pH-und Temperaturänderungen oder durch Licht ausgelöst. Hier stellt sich nun die Frage: Genügt eine einzelne Chromophoreinheit, um dieses responsive Verhalten zu beeinflussen?…”