Dispersible microporous diblock copolymer nanoparticles via polymerisation-induced self-assembly

Microporous materials are predominantly formed as insoluble powders which means that they can be difficult to process. Here we report a new class of solvent-dispersible porous polymers synthesised by reversible addition-fragmentation chain transfer mediated polymerisation-induced self-assembly (RAFT-mediated PISA), formed from the polymerisation of divinylbenzene and fumaronitrile using a poly(ethylene glycol) macromolecular chain transfer agent (PEG macro-CTA). The particles have a dual morphology consisting of smaller spheres of 24-29 nm in diameter aggregated into larger particles of 204-262 nm in diameter. Gas sorption analysis showed the particles to have BET surface areas of 274 to 409 m(2) g(-1) with internal pore sizes centred around 1.8 nm and further larger pores arising from the sphere packing of the aggregates. The particles were found to be photoluminescent (emission lambda(max) = 326 nm) when exposed to UV light which could be quenched by the addition of nitroaromatic compounds, for example, 99% of the emission was quenched in the presence of 38 ppm picric acid.