Self-assembly of amphiphilic block copolymer in water suffers from the undesired encapsulation of hydrophobic reactive motifs in core-forming block, which deteriorates the performance as aqueous catalysts. This problem can be circumvented by polymerisation-induced self-assembly (PISA). Herein, we report a new strategy for one-pot synthesis of reactive block copolymer nanoparticles whose hydrophobic reactive motifs decorate surrounding core-shell interfaces. We demonstrate fast RAFT aqueous dispersion polymerisation of a commercial available specialty monomer, diacetone acrylamide (DAAM), under visible light irradiation at 25 o C. PISA is induced by polymerisation via sequentially dehydration, phase separation and reaction acceleration, and thus complete conversion in 30 min. Replacement of minimal DAAM by NH3 + -monomer induces slight hydration of the core-forming block, and thus a low polydispersity of resultant statistic-block copolymer. Moreover, simultaneous in situ self-assembly and chain growth favours adjustment of newly-added NH3 + -units outward to core-shell interfaces while the major DAAM units collapse to hydrophobic PISA-cores. Both lead to timely and selective self-assembly into the new reactive nanoparticles whose NH3 + -motifs decorate surrounding core-shell interfaces. These nanoparticles well suit fabrication of advanced nanoreactors whose hydrophobic dative metal centres decorate surrounding interfaces via simultaneous imine conversion and Zn(II)-coordination. Such PISA-nanostructures endow hydrophobic metal centres with huge and accessible specific surface area and are stabilized by water-soluble shells. Therefore, this strategy holds fascinating potentials for the fabrication of metalloenzyme-inspired aqueous catalysts.Enzyme inspired interface-decorated media-accessible reactive nanoparticles are now available via PISA by aqueous dispersion RAFT of commodity-DAAM with minimal NH 3 + -monomer.

Analogous to cellulose, polymers whose monomer units possess both hydrogen donators and acceptors are generally insoluble in ambient water because of hydrogen bonding (HB). Herein we present stimuli-responsive long aqueous cylindrical vesicles (nanotubes) synthesized directly using HB-driven polymerization-induced self-assembly (PISA) under visible-light-mediated RAFT aqueous dispersion polymerization at 25 °C. The PISA undergoes an unprecedented film/silk-to-ribbon-to-vesicle transition and films/silks/ribbons formed at low DPs (∼25–85) of core-forming block in free-flowing aqueous solution. Pore-switchable nanotubes are synthesized by electrostatic repulsive perturbation of the HB association in anisotropic vesicular membranes via inserting minor ionized monomer units into the core-forming block. These nanotubes are synthesized at >35% solids, and tubular membranes are more sensitive than spherical counterparts in response to aqueous surroundings. This facile, robust, and general strategy paves a new avenue toward scale-up production of advanced intelligent nanomaterials.

We report an updated polymerization-induced thermal self-assembly (PITSA) [Figg, C. A.; et al. Chem. Sci. 2015, 6, 1230]. The concept is validated using visible light initiated RAFT aqueous dispersion polymerization of diacetone acrylamide monomer at 25 – 70 °C. This PITSA formulation produces block copolymer lamellae at 25 °C while the copolymer morphology evolves from spheres to worms to vesicles during polymerization at 60 °C, which is above the lower critical solution chain length (LCSCL) of the core-forming block. Particle shape and size uniformity can be controlled by reaction temperature using a single photo-PISA formulation. Vesicles-to-lamellae and vesicles-to-worms transitions are achieved in situ upon cooling reaction dispersions (70 °C) to 25 °C, leading to the transformation of initially free-flowing liquids to physical hydrogels. Moreover, reversible thermoresponsive lamellae-to-vesicles-to-lamellae and worms-to-vesicles-to-worms transitions of as-synthesized nanoparticles are achieved in dilution in a heating–cooling cycle. This thermoresponsive photo-PISA formulation updates Figg’s PITSA protocol mainly in three aspects: (1) the absence of LCST limitation, (2) user-friendly control of particle shape and size uniformity by reaction temperature using a single photo-PISA formulation, and (3) reversible thermoresponsive transition of the ketone-functionalized vesicles to customer-guided lamellae or worms.

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We present coordination-driven intramolecular orthogonal self-assembly of ABC triblock copolymer into protein-like compartmentalized SCNP, whose sub-10 nm ultrafine subdomains are discrete and can respond to aqueous surroundings individually.