From A Fundamental Study on Hydrogen Bond Network and Chain Mobility in Benzimidazole Model Compounds to Various Designs and Development of Benzimidazole-based Anhydrous Membranes for Proton Exchange Membrane Fuel Cell

A series of N-containing heterocycles i.e., imidazole and benzimidazole are systematically designed to study how proton transfer in anhydrous system is related to hydrogen bond network and molecular mobility. The work extends to polymers containing heterocycles to clarify the proton conductivity in proton exchange membrane fuel cell (PEMFC)

Thermo-Magnetoresponsive Dual Function Nanoparticles: An Approach for Magnetic Entrapable–Releasable Chitosan

Magnetic polymeric nanoparticles can be used for selective binding in a magnetic field. However, as the magnetic nanoparticles (MAG) are stabilized with polymers, the separation of the MAG from the polymer chains after use is difficult. This work proposes a combination of a thermoresponsive polymer with MAG allows for the as-desired simple removal of MAG from the polymer chains. For this, chitosan (CS) was conjugated with thermoresponsive poly­(<i>N</i>-isopropylacrylamide) (PNIPAM) and antibody (Ab) together with the physisorbed MAG as a thermo-magneto dual functional material. The key synthesis steps are (i) radical polymerization of NIPAM in the presence of mercaptoacetic acid so that the PNIPAM obtained contains terminal carboxylic acid groups (PNIPAM-COOH), (ii) the CS-<i>N</i>-hydroxysuccinamide water-based system that allows conjugation of CS with PNIPAM-COOH in water at room temperature, and (iii) the weak interaction between MAG and the CS chain. As a model application, CS is conjugated with the antirecombinant <i>Leptospirosis</i> Ab (rLipL32) to allow the selective binding and collection of the target antigen under the dual functions. This is the first demonstration of a simple but effective solution for MAG exclusion from the target molecules and will be practical for diverse applications, such as diagnosis, sensors, filtration, etc

Cyclization of aromatic aldehydes and phenylenediamines under reduced pressure: A convenient, environmentally friendly, and simple procedure for benzimidazole precursors

<p>The condensation of phenylenediamines with aromatic aldehydes in the presence of catalysts to obtain benzimidazoles under harsh condition is achieved by various reported conditions. The present work demonstrates a convenient, environmentally friendly, and simple procedure to obtain benzimidazoles through the cyclization between phenylenediamines and aromatic aldehydes under reduced pressure. By simply adding aromatic aldehydes to diaminobenzene derivatives and allowing the stoichiometric reaction at room temperature under reduced pressure at 66.6 Pa, the dehydrogenation leads to benzimidazoles with the yield as high as 80–90%. In addition, the purging of H₂ gas to benzimidazoles results in the hydrogenation of imidazole to obtain the intermediate benzimidazolidine form. This confirms how the cyclization relies on the reduced pressure. This synthesis pathway not only gives the aromatic aldehydes with high yield under the mild condition but also the selection of benzaldehydes with reactive functional groups leads to the precursors for other chemical modifications and polymerizations.</p

“Grafting to” as a Novel and Simple Approach for Triple-Shape Memory Polymers

Maleated-polystyrene-<i>b</i>-poly­(ethylene-co-butylene)-<i>b</i>-polystyrene (m-SEBS) is a block copolymer with two melting temperatures belonging to soft poly­(ethylene-co-butylene) (EB) and hard polystyrene (PS) segments. As EB segments contain anhydride reactive groups, this allows grafting polybutylene succinate (PBS) as another soft segment to m-SEBS backbone to obtain triple-shape memory polymers based on two transition temperatures, i.e., <i>T</i>_m values of EB (at 55–65 °C) and PBS (at 105–115 °C). The present work shows a novel and simple approach of “grafting to” to develop triple-shape memory polymers

“Grafting to” as a Novel and Simple Approach for Triple-Shape Memory Polymers

Maleated-polystyrene-<i>b</i>-poly­(ethylene-co-butylene)-<i>b</i>-polystyrene (m-SEBS) is a block copolymer with two melting temperatures belonging to soft poly­(ethylene-co-butylene) (EB) and hard polystyrene (PS) segments. As EB segments contain anhydride reactive groups, this allows grafting polybutylene succinate (PBS) as another soft segment to m-SEBS backbone to obtain triple-shape memory polymers based on two transition temperatures, i.e., <i>T</i>_m values of EB (at 55–65 °C) and PBS (at 105–115 °C). The present work shows a novel and simple approach of “grafting to” to develop triple-shape memory polymers