Volume 51 Issue 8, August 2019

Microstructured surfaces have been attracting a considerable amount of attention for many practical applications, such as superhydrophobic materials. In this report, vulcanized rubber was focused on as a flexible and durable hydrophobic material for the fabrication of microstructured superhydrophobic surfaces. Superhydrophobic spike-array microstructures were simply prepared from a vulcanized rubber by using a silicon micromold, and the arrangements were reversibly deformed by repeated stretching without destruction of the spikes. Surface wettability can be controlled by stretching the vulcanized rubber, and the phenomenon was theoretically explained by the wettability transition from a Cassie–Baxter to a Wenzel state.

The nanoscale assembly strategies based on the Langmuir–Blodgett (LB) technique were highlighted to demonstrate the potential for functional device fabrication. (1) The assembly of silsesquioxane-containing polymers can be used to produce uniform monolayers, which are precursors of ultrathin SiO₂ films with controlled porosity. (2) The assembly of inorganic nanoparticles and metal-organic framework films on polymer films demonstrates the importance of the spatial alignment of anchoring units. (3) The assembly of π-conjugated units can be used for high-density and low-dimensional assembly.

Categorization of molecular assemblies of primary to quaternary structures is herein proposed with citing typical examples of peptide molecular assemblies for each category. Primary structure; tubes and vesicles, Secondary structure; chimeric morphology, Tertiary structure; phase-separated tubes, Quaternary structure; hierarchical organization of molecular assemblies.

Concentrated poly(ethylene carbonate) (PEC) and poly(trimethylene carbonate) (PTMC) blend electrolytes with 150 mol% of LiFSI were prepared and the PEC₆PTMC₄ electrolyte was applied in all-solid-state Li batteries. The blend electrolyte has an ionic conductivity of 10⁻⁵ S cm⁻¹ and a Li⁺ transference number (t₊) of 0.73. Meanwhile, the PEC₆PTMC₄ electrolyte exhibits a good electrochemical stability with Li electrode than those of PEC and PTMC single-polymer electrolytes. An LFP half-cell exhibits a discharge capacity of 150 mAh g⁻¹ at 50 °C and a C/10 rate.

The aqueous oxidative coupling polymerization of 3,4-ethylenedioxythiophene was conducted in the presence of heptadecafluorooctane sulfonic acid, which was used as a perfluoroalkyl dopant to synthesize hydrophobic poly(3,4-ethylenedioxythiophene) particles. The dried poly(3,4-ethylenedioxythiophene) particles could be used as a near-infrared-responsive liquid marble stabilizer exhibiting light-to-heat conversion properties. The movement of the poly(3,4-ethylenedioxythiophene) particle-coated liquid marbles on a planar water surface was driven by near-infrared laser-induced Marangoni propulsion.

A melittin-targeting drug carrier was synthesized by the grafting of sodium alginate to an oligopeptide. The melittin-loading onto oligopeptide–alginate nanoparticles at 0.1:1 unit ratio was more than double that onto alginate nanoparticles, suggesting the specific interaction of melittin with the oligopeptide-side chain in the oligopeptide–alginate nanoparticles. More than 80% of Caco-2 cells did not survive under the dose of 2.5 μM melittin-loaded oligopeptide–alginate nanoparticles. The results confirm that the derivation of an oligopeptide-side chain in alginate offers a specific binding site for melittin and effectively works in cancer chemotherapy.

We developed flame-retardant thermoplastics directly from biomass just by dissolution into ionic liquids and precipitation. During the dissolution, a phosphonate-type ionic liquid adducted on the polymers included in biomass such as cellulose through reaction of the hydroxyl groups. In this method, more than 86% of the hydroxy groups were maintained after ionic liquid substitution because the single phosphonate-type ionic liquid acted as a plasticizer and flame retardant in the plant biomass. Therefore, the plant biomass-derived flame-retardant thermoplastics have the potential for further functionalization.

The solid-state structure of L₂AlEt is reported by X-ray diffraction. BnOH (1 equiv. to L₂AlEt) selectively reacts with ~0.5 equiv. of L₂AlEt to afford free L–H (~1 equiv.) while maintaining L₂AlEt (~0.5 equiv.). The stoichiometric balance suggests the formation of 0.5 equiv. of (BnO)₂AlEt. The ROP of CL via the synergic catalysis of the two coexistent Al-complexes, L₂AlEt (0.50 mol%) as a Lewis acid activator of CL and (RO)₂AlEt (0.50 mol%) as a nucleophile, is proposed.

Polar polymers with permanent dipoles such as poly(vinylidene fluoride) (PVDF) are suitable for use as high-energy storage density dielectrics because of their high permittivity. This study investigated the ferroelectricity and energy storage behaviors of PVDF Langmuir–Blodgett (LB) nanofilms at sub-50 nm thicknesses. The ferroelectric hysteresis loops were measured using a Sawyer–Tower circuit in different electric fields. An energy density of 6.0 J/cm³ at 500 MV/m was demonstrated for the 12-nm-thick PVDF LB nanofilm device.