In this study, we synthesized (i) a multi-diamidopyridine-functionalized polyhedral oligomeric silsesquioxane (MD-POSS) through nucleophilic substitution and click 1,3-cycloaddition reactions and (ii) both mono-and bis-uracil (U)-functionalized poly(ethylene glycol) derivatives (U-PEG and U-PEG-U, respectively) through Michael additions of U to acryloyl-functionalized PEG oligomers. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) revealed that supramolecular structures self-assembled from mixtures of MD-POSS and U-PEG and from MD-POSS and U-PEG-U. Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy confirmed the presence of multiple hydrogen bonding interactions between the diaminopyridine groups of MD-POSS and the U groups of U-PEG and U-PEG-U. Because of these strong reversible intermolecular multiple hydrogen bonds, the POSS-based polymer-like supramolecular materials exhibited improved thermal properties upon increasing the MD-POSS content.

Eliminating the crystallization ability of PLLA to amorphous PLA block segment allowed us to obtain long-range-ordered mesoporous materials.

Abstract:In this study, we tethered terminal uracil groups onto short-chain poly(ethylene glycol) (PEG) to form the polymers, uracil (U)-PEG and U-PEG-U. Through AC impedance measurements, we found that the conductivities of these polymers increased upon increasing the content of the lithium salt, LiAsF 6 , until the Li-to-PEG ratio reached 1:4, with the conductivities of the LiAsF 6 /U-PEG blends being greater than those of the LiAsF 6 /U-PEG-U blends. The ionic conductivity of the LiAsF 6 /U-PEG system reached as high as 7.81 × 10 −4 S/cm at 30 °C. Differential scanning calorimetry, wide-angle X-ray scattering, 7 Li nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy revealed that the presence of the uracil groups in the solid state electrolytes had a critical role in tuning the glass transition temperatures and facilitating the transfer of Li + ions.