Isolated In Situ Cross-Linking-Assisted Polymerization-Induced Self-Assembly to Polymer Cubosomes with Enhanced Stability

Polymer cubosomes (PCs) are promising porous materials, but suffer from unstable structures under harsh chemical conditions. Herein, we report a robust “shaping-isolating-cross-linking” strategy that combines polymerization-induced self-assembly (PISA) with sequential separation and then in situ cross-linking to enhance the stability of polystyrene-based (PS-based) PCs. Taking poly(hydroxypropyl methacrylate) (PHPMA) as the stabilizer, PS-based PCs were first synthesized via reversible addition–fragmentation chain transfer (RAFT) polymerization-mediated PISA in ethanol, yielding well-defined Im3̅m bicontinuous structures. Subsequently, these PCs were isolated from the PISA system and then used as seeds to fabricate cross-linked PCs using divinylbenzene (DVB) as the cross-linker by RAFT dispersion polymerization. The cross-linked PCs preserved their original bicontinuous morphologies, and their resistance to organic solvents and high temperatures was significantly enhanced. This approach can be applied to systems with stabilizers containing pyridine groups and cross-linkers involving disulfide bonds, exhibiting recyclable catalytic and stimuli-responsive performances in organic solvents, respectively. We believe that this work establishes a scalable platform for stabilizing complex porous morphologies and broadening their applications.