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Block copolymer (BCP) self-assembly is a versatile technique in the preparation of polymeric aggregates with varieties of morphologies. However, its morphology library is limited. Here, the discovery of pincushion of tubules is reported for the first time, via BCP self-assembly of poly(4-vinylpyridine)-b-polystyrene (P4VP-b-PS) with very high molecular weight (500 kDa) and asymmetry (2 mol% P4VP). The investigation confirms the importance of core-forming block length on morphology control of BCP self-assemblies, especially with respect to tubular structures. The morphology landscape of tubular structures is successfully established, where dumbbell of tubule, tubule, loose clew of tubules, tight clew of tubules, and pincushion of tubules can be prepared by adjusting the core-forming block length. This work therefore expands the structure library of BCP self-assemblies and opens up a new avenue for the further applications of these tubular materials.

A facile synthetic pathway for preparing block copolymers with pH-responsive L-glutamic acid segments for membrane disruption is reported. Aqueous reversible addition-fragmentation chain transfer (aRAFT) polymerization was first used to prepare biocompatible, nonimmunogenic poly[N-(2-hydroxypropyl)methacrylamide]. This macro chain transfer agent (CTA) was then converted into a macroinitiator via simultaneous aminolysis and thiol-ene Michael addition using the primary amine substituted N-(3-aminopropyl)methacrylamide. This macroinitiator was subsequently utilized in the ring-opening polymerization of the N-carboxyanhydride monomer of γ-benzyl-L-glutamate. After deprotection, the pH-dependent coil-to-helix transformations of the resulting HPMA-b-(L-Glu) copolymers were monitored via circular dichroism spectroscopy. HPMA segments confer water solubility and biocompatibility while the L-glutamic acid repeats provide reversible coil-to-helix transitions at endosomal pH values (~5-6). The endolytic properties of these novel [HPMA-b-(L-Glu)] copolymers and their potential as modular components in drug carrier constructs was demonstrated utilizing red blood cell hemolysis and fluorescein release from POPC vesicles.

A facile strategy for control of the polymer topologies can be achieved simply by tuning the feed molar ratio of catalyst to transfer agent in the controlled radical polymerization.

A series of well-defined diblock copolymers, poly(ethylene oxide)-block-poly(4-vinylpyridine) (PEO-b-P4VP) used as physical coating of capillaries, were synthesized by atom transfer radical polymerization (ATRP). EOF measurement results showed that all synthesized PEO-b-P4VP diblock copolymer-coated capillaries in this report could suppress EOF effectively compared to the bare fused-silica capillaries, and efficient separations of basic proteins were achieved. The effects of the molecular weight of P4VP block in PEO-b-P4VP and buffer pH on the separation of basic proteins for CE were investigated in detail. Moreover, the relationships between morphologies of PEO-b-P4VP diblock copolymers in buffer, which were studied by transmission electron microscopy, and the separation efficiencies of basic protein with PEO-b-P4VP diblock copolymers coatings were discussed.

A novel strategy for preparation of multiple nanostructural materials, which is the creation of such materials directly from controlled radical dispersion polymerization in one pot, has been developed. In the formation of polymeric nanomaterials, the chain length ratio of the hydrophobic to hydrophilic blocks is altered continuously, which induces two phase transitions, phase separation to form spherical micelles and re-organization of the resulting spheres to yield multiple morphologies including nanorods, nanotubes, vesicles and doughnuts. This is quite different from self-assembly of the block copolymer in a selective solvent, where nature and solubility parameter of the solvents are changed. In the reversible addition-fragmentation chain transfer (RAFT) polymerization of styrene in methanol using poly(4-vinylpyridine) as macro RAFT agent, the resultant polymeric nanomaterials with various morphologies coexisted generally, however, uniform nanowires and vesicles could be prepared by appropriately selecting concentration of monomer and feed ratio, as well as by strict control of reaction conditions. One advantage of this strategy is that the nanomaterials with a concentration as high as 0.5 g mL−1 can be achieved, this provides possibility for studying extensive applications of the various nanomaterials.

Polymerization-induced self-assembly and re-organization (PISR) was used to prepare polymeric nanostructured materials with a variety of morphologies. Reversible addition-fragmentation chain transfer (RAFT) polymerization of styrene in a selective solvent, methanol, was carried out using cyanoisopropyl dithiobenzoate-terminated poly(2-dimethylaminoethyl methacrylate) (PDMAEMA-DBT) as the macro chain transfer agent and stabilizer for investigation of the factors influencing the formation of morphologies. Various morphologies, including spherical micelles, nanostrings, vesicles and large compound vesicles, with different shapes were obtained by changing the feed ratios and reaction conditions. The sequential morphologic transitions from spherical micelles to nanostrings, to vesicles and to large compound vesicles via increasing the chain length ratio of the hydrophobic block to the hydrophilic one in the same system were observed for the first time. This approach can be performed at a high concentration, thus it can be scaled up for the reproducible preparation of nanostructured materials in a relatively high volume.

A simple and facile strategy has been developed for synthesis of nanomaterials via polymerization in high concentration; multiple morphologies can be created and tuned just by variation of the feed ratio and reaction conditions.