Polymer Assemblies with Nanostructure-Correlated Aggregation-Induced Emission

Abstract

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.

Photoinitiated Seeded RAFT Dispersion Polymerization: A Facile Method for the Preparation of Epoxy‐Functionalized Triblock Copolymer Nano‐Objects

“…Over the past decade, polymerization‐induced self‐assembly (PISA) of block copolymers via reversible addition–fragmentation chain transfer (RAFT)‐mediated dispersion polymerization has enabled block copolymer nano‐objects with a diverse set of complex morphologies to be synthesized at high solids content (up to 50%) . However, the RAFT‐mediated PISA is typically conducted at high temperatures (e.g., 70 C) by thermal initiation, which is not beneficial for the preparation of temperature sensitive polymer nano‐objects (e.g., protein–polymer conjugate).…”

Aggregation‐Induced Emission for Visualization in Materials Science

“…The assemblyi nto the micelles has also been confirmed and studied with polymers through polymerization-induced self-assembly (PISA) in selected solvents. [36] The morphological evolution involving spherical micelles,w orm-like micelles, and vesicles can be visualized based on AIE-activep olymers. Moreover, the fluorescent intensities and quantum yields of the assembled micelles showedacorrelation with the AIE molecules.…”

Overcoming Kinetic Trapping for Morphology Evolution during Polymerization‐Induced Self‐Assembly

“…Armes and coworkers have studied and addressed it as kinetic trapping, which is caused by the strong repulsions between long PDMA 51 stabilizers preventing the fusion and reorganization of nanoparticles . Contrarily, using short stabilizer of PDMA 33 ‐CTA, D 33 ‐ b ‐B 106 copolymers are vesicles …”

“…[44,49] Contrarily, using short stabilizer of PDMA 33 -CTA, D 33 -b-B 106 copolymers are vesicles. [58] To overcome kinetic trapping, we introduce a solvophilic comonomer (TESPMA) into the RAFT dispersion copolymeri-zation ( Figure 1e). The feed ratio of TESPMA/BzMA is maintained as 1/8; while the DP increases, D 51 -b-(B 160 -co-T 15 ) and D 51 -b-(B 203 -co-T 17 ) form worms, and D 51 -b-(B 380 -co-T 31 ) are vesicles as shown in Figure 1f-h.…”