Polyurethane-Based Ionogels Exhibiting Durable Thermoresponsive Optical Behavior Under High-Temperature Conditions.

Polyurethane (PU)-based transparent and flexible ionogels, showing unusual thermo-responsive optical properties, were successfully prepared by mixing PU-precursor and a hydrophobic ionic liquid, 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (EMIM-TFSI). Although the initial ionogels were transparent at room temperature, significant increases in opacity were observed with increasing temperature up to 120°C, because of macroscopic phase separation of the PU-matrix and hydrophobic EMIM-TFSI. In addition, the optical transition temperature could be arbitrarily controlled simply by varying the mixing ratio of EMIM-TFSI within the PU-matrix.

Self-Healing Superhydrophobic Materials Showing Quick Damage Recovery and Long-Term Durability.

Superhydrophobic coatings/materials are important for a wide variety of applications, but the majority of these man-made coatings/materials still suffer from poor durability because of their lack of self-healing ability. Here, we report novel superhydrophobic materials which can quickly self-heal from various severe types of damage. In this study, we used poly(dimethylsiloxane) (PDMS) infused with two liquids: trichloropropylsilane, which reacts with ambient moisture to self-assemble into grass-like microfibers (named silicone micro/nanograss) on the surfaces and low-viscosity silicone oil (SO), which remains within the PDMS matrices and acts as a self-healing agent.

Transparent gel composite films with multiple functionalities: Long-lasting anti-fogging, underwater superoleophobicity and anti-bacterial activity.

Transparent gel-based composite films with multiple functionalities, showing long-lasting anti-fogging properties, underwater superoleophobicity, and anti-bacterial activity were successfully prepared from polyvinylpyrrolidone (PVP) and aminopropyl-functionalized clay (AMP-clay). Due to the addition of glutaraldehyde (GA, cross-linker) into the PVP matrices, and AMP-functionalities to the substrate surfaces, both the adhesion properties in water and durability of the anti-fogging properties were significantly improved. In addition, this durability was also found to be markedly improved by increasing the film thickness via deposition of several PVP/AMP/GA layers, while still retaining excellent transparency.

Anti-Fogging/Self-Healing Properties of Clay-Containing Transparent Nanocomposite Thin Films.

Highly transparent antifogging films were successfully prepared on various substrates, including glass slides, silicon, copper and PMMA, by spin-coating a mixture of polyvinylpyrrolidone and aminopropyl-functionalized, nanoscale clay platelets. The resulting films were superhydrophilic and showed more than 90% transmission of visible light, as well as excellent antifogging and self-healing properties.

Continuous, High-Speed, and Efficient Oil/Water Separation using Meshes with Antagonistic Wetting Properties.

We report a novel oil/water separation device, allowing continuous, high-speed, and highly efficient purification of large volumes of oily water. This device uses a pair of hydrophilic/hydrophobic polymer-brush-functionalized stainless steel meshes, which have antagonistic wetting properties, i.e.

Polymer Brush Surfaces Showing Superhydrophobicity and Air-Bubble Repellency in a Variety of Organic Liquids.

Silicon (Si) substrates were modified with polyalkyl methacrylate brushes having different alkyl chain lengths (C(n), where n = 1, 4, 8, and 18) using ARGET-ATRP at ambient temperature without purging the reaction solution of oxygen. The dynamic hydrophobicity of these polymer brush-covered Si surfaces when submerged in a variety of organic solvents (1-butanol, dichloromethane, toluene, n-hexane) depended markedly on the alkyl chain length and to a lesser extent polymer solubility. Long-chain poly(stearyl methacrylate) brushes (C(n) = 18) submerged in toluene showed excellent water-repellant properties, having large advancing/receding contact angles (CAs) of 169°/168° with negligible CA hysteresis (1°).

Synthesis and confinement of carbon dots in lysozyme single crystals produces ordered hybrid materials with tuneable luminescence.

The synthesis and confinement of graphitic nanoparticles (carbon dots) in the nanoscale solvent channels of cross-linked lysozyme single crystals is used to prepare novel biohybrid luminescent materials. Co-sequestration of acridine orange within the biohybrid crystals from acidic or neutral solutions yields FRET-mediated phosphors emitting white or green light, respectively. The results offer a route to new types of tuneable multicolour luminescent materials based on microcrystalline host-guest energy-transfer systems.

Fabrication of polypyrrole nano-arrays in lysozyme single crystals.

A template-directed method for the synthesis and organization of partially oxidized polypyrrole (PPy) nanoscale arrays within the solvent channels of glutaraldehyde-cross-linked lysozyme single crystals is presented. Macroscopic single crystals of the periodically arranged protein-polymer superstructure are electrically conductive, insoluble in water and organic solvents, and display increased levels of mechanical plasticity compared with native cross-linked lysozyme crystals.