The correlation of aggregation-induced emission (AIE) to the nanostructure of polymer assemblies was investigated. A series of AIE-active PDMA-b-P­(BzMA-TPE) [PDMA: poly­( N , N -dimethyl­aminoethyl methacrylate); P­(BzMA-TPE): poly­[benzyl methacrylate-co-1-ethenyl-4-(1,2,2-triphenyl­ethenyl)­benzene]] assemblies with controlled nanostructures were prepared via polymerization-induced self-assembly of BzMA and TPE, an AIEgen, in the presence of PDMA macro-chain-transfer agents. We found that the fluorescence intensity and fluorescent quantum yield increase in the order of vesicles > wormlike micelles > spherical micelles. For spherical micelles and vesicles, the AIE effect strengthens with increase in micellar size and wall thickness, respectively. As the AIE effect indicates the packing compactness of the AIEgens, the discovered structure-correlated emission can be attributed to the stress variation of polymer chains in the aggregates. AIE is therefore potentially useful as a probe for the investigation and understanding of nanostructure and evolution process of polymer self-assemblies.

A series of azo-containing copolymeric assemblies based on poly­( N , N -dimethyl­aminoethyl methacrylate)-b-poly­[(benzyl methacrylate)-co-(4-phenyl­azophenyl methacrylate)] [PDMA-b-P­(BzMA-co-AzoMA)] were prepared by reversible addition–fragmentation chain transfer polymerization-induced self-assembly at high solid contents. Depending on the chain length of P­(BzMA-co-AzoMA), spheres, worms, and vesicles were readily prepared. These azo-containing wormlike micelles underwent reversible worm-to-vesicle transformation upon alternative UV/vis light irradiation. By investigating the morphology evolution, a series of intermediates were observed, including coalesced worms as well as “octopus”-like and “jellyfish”-like structures. The morphology transformation was rationalized by the volume change of the P­(BzMA-co-AzoMA) block caused by the trans–cis isomerization of the azobenzene groups. It is the first demonstration of light-stimulated reversible worm-to-vesicle transition and would benefit for the understanding of morphology evolution of polymer assemblies under external stimuli.

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A CO 2 -responsive well-defined magneto-polymeric drug delivery system has been developed.An dosing release of doxorubicin (DOX) in vitro in a time-controllable manner can be easily executed under alternative CO 2 /N 2 treatment by these smart nanocarriers.CO2-resonsive well-defined core-shell-corona structure magnetic Fe3O4@SiO2-poly(N,Ndimethylaminoethyl methacrylate) (PDMAEMA) nanocarriers have been developed as efficient drug delivery system. The hybrid magnetic nanoparticles (MNPs) demonstrated a sandwich structure and high super-paramagnetic, biocompatibility properties as well as gas-responsive behavior. We found that the hydrodynamic radius (Rh) of the magnetic hybrid nanoparticles could be adjusted by alternate CO2/N2 treatment driving a switchable volume transition from contraction to expansion because of the CO2 responsiveness of PDMAEMA. The CO2-triggered protonation of the polymer shell gives rise to obvious zeta potential change of the nanoparticles. Importantly, the CO2 induced reversible "on-off" transformation makes it possible to perform an dosing release of doxorubicin (DOX) in vitro in a time-controllable manner which is of great significance in controlled drug release. In the presence of CO2, the drug release rate is significantly accelerated; while low drug release could be achieved by removal of CO2 using N2. Moreover, in vitro cytotoxicity represented that the CO2-responsive magnetic nanocarries have good biocompatibility and could be safely used in living systems.