Direct Synthesis of Polymer Vesicles on the Hundred‐Nanometer‐and‐Beyond Scale Using Chemical Oscillations

Abstract

The direct synthesis of block copolymer vesicles on the scale of tens to hundreds of nanometers using reversible addition-fragmentation chain transfer (RAFT) dispersion polymerization as an effect of chemical oscillations is reported. RAFT polymerization is successfully accomplished between polyethylene glycol containing a RAFT agent (PEG-CTA) and ethyl acrylate monomer in the presence of the Belousov-Zhabotinsky (B-Z) reaction in oscillatory mode. The self-assembly of poly(ethylene glycol)-b-poly(ethyl acrylate) unimers gives rise to spherical micelles. The self-assembled micelles reorganize and transform to vesicles. All the chemistry of polymerization, self-assembly and self-organization, of macromolecules takes place in a single pot using only a few simple raw materials in aqueous solution.

PISA: construction of self-organized and self-assembled functional vesicular structures

“…As mentioned previously, the redox oscillatory BZ reaction can be applied to PISA as a vehicle for using chemicals as a fuel to produce the radicals for RAFT polymerization. 26,27,82 The BZ reaction consists of the oxidation of an organic species, typically malonic acid, by the bromate species of a strong acid, in the presence of a redox catalyst e.g. tris(bipyridine)ruthenium(II) chloride that can oscillate between two redox states.…”

Concurrent self-regulated autonomous synthesis and functionalization of pH-responsive giant vesicles by a chemical pH oscillator

“…[25][26][27][28][29][30] Among the about 200 known oscillating chemical reactions, 31 the Belousov-Zhabotinsky redox oscillator was the first with which micelles and vesicles made of various ABCs have been generated using PISA in batch and continuously stirred-tank reactors (CSTR). [25][26][27]29,30 Then PISA initiated by a chemical pH oscillator (represents a different family of oscillatory chemical reactions), specifically by the semibatch BrO 3 À -SO 3 2À chemical oscillator has been demonstrated by us. 28 Chemical oscillators provide remarkable examples of transient self-assembly regulating chemical fuels.…”

Novel Routes for the Synthesis of a Thermoresponsive Polymer: A Comparative Approach

“…In conventional method polymer was synthesized by solution free radical polymerisation for 5 hours at 80 °C with nitrogen bubbling and in presence of initiator. In BZ method, the free radicals generated as reaction intermediates were explored as initiators instead of using thermo initiator or photo initiator for the synthesis of polymer [42–43] . The free radicals generated in BZ reaction which are otherwise harmful get easily consumed during the synthesis of polymer.…”