Compared with the post-polymerization cross-linking strategy, in situ cross-linking by divinyl comonomers in polymerization-induced self-assembly (PISA) is a more straightforward and convenient approach to produce structurally stabilized nano-objects. However, cross-linking...

Polymerization-induced self-assembly (PISA) has been demonstrated to be a powerful strategy for producing polymeric nano-objects. Polymeric nanotubes with hollow and anisotropic structures have attracted great interest in materials science. However, according to the theoretical prediction of the packing parameter, polymeric nanotubes are hard to be produced by the self-assembly of block copolymers, which may be due to the lack of directionality of solvophobic interactions. Herein, we demonstrate that aromatic interactions between the solvophobic blocks facilitate the formation of polymeric nanotubes. Polymeric nanotubes with a remarkable length (>11 μm) are generated in the reversible addition−fragmentation chain transfer (RAFT) dispersion polymerization of the aromatic monomer 2-(methacryloyloxy) ethyl anthracene-9-carboxylate (MAEAC) using poly(ethylene glycol) as the macro RAFT agent (PEG 45 -CPADB). When the aromatic interactions of the membrane-forming blocks are weakened by high temperature or copolymerization of MAEAC with a weakly aromatic monomer 2-(methacryloyloxy)ethyl benzoate (MAEB), spherical nano-objects instead of nanotubes tend to be produced. The concentration of polymer chains also plays a vital role in the formation of polymeric nanotubes. The aspect ratio of the polymeric nanotubes can be adjusted by controlling the polymer concentration without varying the polymer composition, and polymeric nanotubes with a larger aspect ratio tend to be generated at higher concentrations of block copolymers. The formation of polymersomes with different aspect ratios for a given polymer provides significant opportunities to investigate the shape-determined performances of the polymersomes while eliminating the influence of polymer composition.

Worm‐like micelles have attracted great interest due to their anisotropic structures. However, the experimental conditions for obtaining worm‐like micelles are very restricted, which usually causes seriously poor reproducibility. In this work, significantly enhanced accessibility of worm‐like micelles is realized by in situ crosslinking polymerization‐induced self‐assembly (PISA). The reproducibility of worm‐like micelles is greatly improved due to the significantly enlarged experimental windows of worm‐like micelles in the morphology diagram. Moreover, the reliability of the methodology to enhance the accessibility of worm‐like micelles has been demonstrated in various in situ crosslinking PISA systems. The greatly enhanced accessibility and reproducibility of worm‐like micelles is undoubtedly cost‐effective especially in scale‐up production, which paves the way for further application of worm‐like micelles with various compositions and functionalities.

Comprehensive Summary The size and size distribution of polymeric nanoparticles have great impact on their physicochemical and biological properties. Polymerization‐induced self‐assembly (PISA) has been demonstrated to be an efficient method to fabricate various polymeric nanoparticles, among which polymeric vesicles have attracted great interest due to their unique hollow structure. However, polymeric vesicles with relatively broad size distributions and random size are normally formed, which is problematic for many potential applications. Herein, we report the synthesis of polymeric vesicles with low‐polydispersity and controllable size by polymerization‐induced self‐assembly. A mixed macro RAFT agent of three different poly(ethylene glycol) (PEGm‐CPADB) was used to mediate the RAFT dispersion copolymerization of 7‐(2‐methacryloyloxyethoxy)‐4‐methylcoumarin (CMA) and benzyl methacrylate (BzMA), which generated vesicles with low‐polydispersity (< 0.1) and controllable size in the scope of sub‐100 nm. In comparison, RAFT dispersion copolymerization of CMA and BzMA using a single PEG‐CPADB as the macro RAFT agent generated vesicles with adjustable but obviously larger size and broader size distributions (> 0.1). The results demonstrate that the ternary stabilizers play a crucial role in the formation of small and low‐polydispersity vesicles.