Steric effects in light-induced solvent proton abstraction

The significance of solvent structural factors in the excited-state proton transfer reactions of the super photobase FR0-SB with alcohols is examined using steady-state and time-resolved spectroscopy and quantum chemistry computations.

A Spectroscopic Study of Solid-Phase Chitosan/Cyclodextrin-Based Electrospun Fibers

In this study, chitosan (chi)/hydroxypropyl-β-cyclodextrin (HPCD) 2:20 and 2:50 Chi:HPCD fibers were assembled via an electrospinning process that contained a mixture of chitosan and HPCD with trifluoroacetic acid (TFA) as a solvent. Complementary thermal analysis (thermal gravimetric analysis (TGA)/differential scanning calorimetry (DSC)) and spectroscopic methods (Raman/IR/NMR) were used to evaluate the structure and composition of the fiber assemblies. This study highlights the multifunctional role of TFA as a solvent, proton donor and electrostatically bound pendant group to chitosan, where the formation of a ternary complex occurs via supramolecular host–guest interactions. This work contributes further insight on the formation and stability of such ternary (chitosan + HPCD + solvent) electrospun fibers and their potential utility as “smart” fiber coatings for advanced applications.

Synthesis of Poly(1-vinyl-1,2,4-triazole) and Preparation of Proton Conducting Membrane for High Temperature Operation

Polymer poly (1-vinyl-1,2,4-triazole) have been synthesized via free radical polymerization using the monomer 1-vinyl-1,2,4-triazole and the initiator azobisisobutyronitrile (AIBN) in toluene as solvent. Proton conducting membranes were prepared by adding nitrilotri (methyl triphosphonic acid) as a dopant into a solution of poly (1-vinyl-1,2,4-triazole) at various molar ratios. The mixture was cast in polished poly (tetrafluoroethylene), PTFE plates and the solvent was evaporated carefully at temperatures of 50 °C for 12 hours. Interaction between the polymer and the dopants have been studied through; FTIR spectrum, thermogravimetric analysis (TG), glass transition temperature using DSC and proton conductivity of membranes made using dielectric-impedance analyzer Novocontrol. Proton conductive membranes with molar ratio of 0.25 was obtained proton conductivity of 8.52 x 10-4S/cm at 150°C.