The self-assembly of a rod-coil amphiphilic block copolymer (ABCP) led to Im3‾ m and Pn3‾ m polymer cubosomes and p6mm polymer hexasomes. This is the first time that these structures are observed in a rod-coil system. By varying the hydrophobic chain length, the initial concentration of the polymer solution, or the solubility parameter of the mixed solvent, head-tail asymmetry is adjusted to control the formation of polymer cubosomes or hexasomes. The formation mechanism of the polymer cubosomes was also studied. This research opens up a new way for further study of the bicontinuous and inverse phases in different ABCP systems.

A series of brush block copolymers (BBCPs) with polynorbornene backbones containing poly{2,5-bis[(4-methoxyphenyl)oxycarbonyl]styrene} (PMPCS, which is a rigid chain) and poly(ethylene oxide) (PEO) side chains were synthesized by tandem ring-opening metathesis polymerizations. The weight fractions of PEO in BBCPs are similar, and the degrees of polymerization (DPs) of PEO side chains are the same while the DPs of PMPCS are different. The bulk self-assembling behaviors were studied by small-angle X-ray scattering (SAXS). The neat BBCPs cannot form ordered nanostructures. However, after the doping of lithium salt, the BBCPs self-assemble into lamellar (LAM) structures. When the DPs of the PEO and PMPCS side chains are similar, the LAM structure is more ordered, which is attributed to the more flat interface between PMPCS and PEO phases. The ionic conductivity (σ) values of the BBCP/lithium salt complex with the most ordered LAM structure at different temperatures were measured. The σ value increases with increasing temperature in the range of 40-200 °C, and the relationship between σ and T fits the Vogel-Tamman-Fulcher (VTF) equation. The σ value at 200 °C is 1.58 × 10 S/cm, which is one of the highest values for PEO-based polymer electrolytes. These materials with high σ values at high temperatures may be used in high-temperature lithium ion batteries.

An amphiphilic alternating copolymer brush (AACPB), poly{(styrene-g-poly(ethylene oxide))-alt-(maleimide-g-poly{2,5-bis[(4methoxyphenyl)oxycarbonyl]styrene})}(P{(St-g-PEO)-alt-(MI-g-PMPCS)}), was synthesized by alternating copolymerization of styreneterminated poly(ethylene oxide) (St-PEO) and maleimide-terminated poly{2,5-bis[(4-methoxyphenyl)-oxycarbonyl]styrene} (MI-PMPCS) macromonomers using the "grafting through" strategy. 1 H NMR and gel permeation chromatography coupled with multiangle laser light scattering were used to determine the molecular characteristics of AACPBs. Although these AACPBs cannot microphase separate with thermal and solvent annealing methods, they can form lamellar structures by doping a lithium salt. This is a first report on lithium salt-induced microphase separation of AACPBs, and the lithium salt-doped AACPBs can serve as solid electrolytes for the transport of lithium ion. For the same AACPB, the ionic conductivity (σ) increases with increasing doping ratio. In addition, σ values of different AACPBs with the same doping ratio become higher for shorter PMPCS side chains. The σ value of the lithium salt-doped AACPB increases with increasing temperature in the range of 25−240 °C, and σ is 1.79 × 10 −4 S/cm at 240 °C. The relatively high σ values of the lithium-doped AACPBs at high temperatures benefit from the rigid PMPCS side chain and the AACPB architecture. The lithium salt-doped AACPBs have the potential to serve as solid electrolytes in high-temperature lithium ion batteries.

The preparation of sub-5 nm ordered structures is very important to the development of today’s nanotechnology. Block molecules have the potential to form structures with significantly small characteristic dimensions. Herein...

A block copolymer containing a liquid crystalline polymer and a poly(ionic liquid) self-assembles and can be used as a solid electrolyte.

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A polynorbornene-based mesogen-jacketed liquid crystalline polymer (MJLCP) containing polyhedral oligomeric silsesquioxane (POSS) in the side chain, PNb10POSS, was synthesized through ring-opening metathesis polymerization. The chemical structure of the monomer was confirmed by 1 H/ 13 C NMR, high-resolution mass spectrometry, and elemental analysis. Molecular characterizations on the polymer were performed with 1 H NMR, gel permeation chromatography, and thermogravimetric analysis. The phase behavior of this new organic-inorganic hybrid polymer was investigated by differential scanning calorimetry, 2 polarized light microscopy, one-dimensional wide-angle X-ray scattering, synchrotron-radiation SAXS, two-dimensional wide-angle X-ray diffraction, and high-resolution transmission electron microscopy. With the competitive self-assemblies of the two covalently connected building blocks, namely MJLCP and POSS moieties, PNb10POSS shows various phase structures including an angstrom POSS crystal (Cr), a hexagonal columnar (Col h ) phase and the Cr coexisting, and the Col h phase at different temperatures. The POSS crystal has a tremendous effect on the liquid crystalline (LC) behavior of the MJLCP. The results show that the competition between the crystallization of POSS and the LC formation of the polymer as a whole results in the complex phase behavior of the MJLCP-based nanohybrid. The polymer self-assembles into an organic-inorganic hybrid inclusion complex on the sub-10 nm scale. This work provides a new approach for the design and synthesis of ordered structures constructed by self-assembly on the sub-10 nm scale.

Supramolecular liquid crystalline block copolymers prepared via hydrogen bonding exhibit hierarchical structures that can be tuned by varying the molar ratio of the discotic hydrogen-bonding acceptor to the block copolymer donor.