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Hydrophobic cryogels with monolithic supermacropores based on poly-trimethylolpropane trimethacrylate (pTrim) containing 1-(2-Hydroxyl-5-nonyphenyl)ethanone oxime (LIX84-I) were successfully prepared by a cryo-polymerization technique using organic solvents with freezing points between room temperature and around 0 °C as solvents. The prepared cryogels were characterized in terms of macroscopic shape and porous structure. The cryogels had a monolithic supermacroporous structure and high contents of LIX84-I depending on the added amount of the extractant to the monomer solution. The amount of LIX84-I impregnated in the cryogel had a linear relationship with the added amount of LIX84-I in the monomer solution for cryo-polymerization. Cu(II) in the aqueous solution was immediately adsorbed into the cryogel containing LIX84-I.

We have investigated the versatility of a two-step preparation method, without a detergent, that combines both the inverse Leidenfrost effect and the cryogelation technique by using the macroporous particles of different kinds of monomers (four vinyl monomers) or a natural polymer (agarose). First, the precursor of polymers was dropped into liquid nitrogen to prepare the spherical frozen droplet by the inverse Leidenfrost effect. Second, the frozen droplets were cryo-polymerized at the frozen temperature; then, cryogel particles were prepared after thawing. Subsequently, the basic characteristics of the macroporous polymer particles obtained above were compared, focusing on the appearances, porous morphologies, and mechanical properties. It was found that the similar polymer particles could be obtained by the two-step preparation method, while there was a slight difference in their characteristics, depending on the type of monomers. Especially for the mechanical properties, the cryogel particles of the hydrophilic polymer exhibited a shape memory function with sponge-like elasticity, whereas the hydrophobic polymer particles were observed to be cracked after compression (i.e., no shape memory function). This work provides a versatile method of adopting various kinds of monomers and natural polymers for the preparation of macroporous particles. Hence, the method possibly has a potential to prepare and design "tailor-made" macroporous polymer particles for the application purpose., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Chiral selective adsorption of L-amino acid, tryptophan (Trp) was achieved using phospholipid membrane-coated porous polymer particles (PPPs). PPPs with numerous pores were prepared by in situ polymerization of divinylbenzene, and then coated with 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC, L-phospholipid) via the impregnation method. Elemental mapping of energy dispersive X-ray (EDX) analysis revealed that DPPC molecules were distributed to the surface and the inner part of PPPs, where almost all the DPPC molecules applied for impregnation were deposited on PPPs. The phospholipid membrane properties of DPPC-PPPs were characterized using the fluorescence probe 6-lauroyl-2-dimethylaminonaphthalene (Laurdan). The results show that DPPC-PPPs possessed a lipid membrane-like environment similar to pure DPPC liposomes, especially at temperatures below 35 °C. DPPC-PPPs slightly adsorbed L-Trp and D-Trp at 45 °C, while DPPC-PPPs significantly adsorbed L-Trp but not D-Trp at 30 °C: enantio excess (e.e.) was 75.0%. The time course of Trp adsorption was investigated: for both enantiomers, similar adsorption behaviors were observed for 30 h, thus suggesting surface adsorption onto DPPC-PPPs. L-Trp adsorption continued after 30 h, suggesting that L-Trp could be distributed in the inner part of DPPC-PPPs. Interestingly, the reused DPPC-PPPs featured improved adsorption performance, suggesting that the deposited DPPC membranes on PPPs could act as chiral selectors for L-Trp. The optical resolution of L-/D-Trp was performed using DPPC-PPPs, resulting in the e.e. of D-Trp was > 60%. Thus, DPPC-PPPs have the potential of chiral selective adsorption of L-amino acid, which can be used as chiral separation materials., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Pd cathode catalysts for polymer electrolyte fuel cells have been covered with silica layers a few nanometres thick. The silica-coated Pd catalysts showed high activity and excellent durability for the oxygen reduction under the severe cathode conditions of PEFCs, while Pd catalysts without silica-coating were seriously deactivated under the same conditions. The coverage of Pd metal with silica prevents the diffusion of Pd species out of the silica layers.

The degree of dynamic morphological change of murine embryonic stem cells is investigated through direct observation by microscopy. As a result, we find that the degree of dynamic morphological change is proportional to the increase in the ratio of the cellular population in subculture.

Monodispersed polymer/polydiacetylenecomposite particles were synthesized by soap-free seeded emulsion polymerization of styrene andmethyl methacrylate; the products were characterized by XRD, SEM, TEM, UV-visible spectroscopy, and single particle scattering spectroscopy. In the synthesis process, polydiacetylene nanocrystals were found to act as inhibitor, and consequently a relatively low concentration was necessary. Different monomers lead to the differences in reaction condition and particle morphology; the PMMA composite particles were simpler in preparation than polystyrene particles, but the latter havebetter spherical morphology. The composite particles were composed of polymer shells and polydiacetylene cores, which kept their crystal structure and optical properties. A high percentage of cored particles could be achieved with optimized reaction conditions where the amount of seed was sufficient and the oily oligomer by-product was suppressed.