Leakage-Proof Electrolyte Chemistry for a High-Performance Lithium-Sulfur Battery

Electrolyte leakage is a severe safety concern in lithium batteries. With highly volatile 1,2-dimethoxyethane as solvent, the leakage related hazards are more pronounced in lithium-sulfur (Li-S) batteries. To address this concern, a leakage-proof electrolyte is delicately designed through functionalizing the commercial electrolyte by Li₆ PS₅ Cl-grafted poly(ethyl cyanoacrylate), which can interact readily with the aluminum-plastic packing through hydrogen bond to immobilize the electrolyte. The moisture from ambient can also catalyze a further polymerization of the macromolecules to seal the leaking points and thereby to solve the leakage issue, endowing Li-S batteries superior safety even in an artificial cut pouch cell. With a bare S loading of 4.9 mg cm^-2 , the battery can deliver good endurance owing to the suppressed polysulfide shuttle by its polar groups. This work enlightens the design of leakage-proof electrolyte and makes a milestone for high performance Li-S batteries.

Ibuprofen Release from Poly(ethyl cyanoacrylate) Nanoparticles Prepared by Semicontinuous Heterophase Polymerization

Ibuprofen-loaded poly(ethyl cyanoacrylate) nanoparticles were prepared by semicontinuous heterophase polymerization of ethyl cyanoacrylate in the presence of ibuprofen; different surfactant concentration, pH, and temperature were used. Particle size was measured by quasi-light scattering and transmission electron microscopy, while the amount of drug released was determined by UV spectroscopy. Nanoparticles with diameters between 10 and 58 nm, loaded with ibuprofen, were obtained. The smallest particles and the higher drug loading were obtained at the highest pH tested. The analysis of the release data showed that the drug release profiles correspond to the Weibull model. Moreover, it was found that most of the ibuprofen is released within the first 80–120 min; initially the release rate is slow, but then it increases to finally decrease. This behavior contrasts with the reported burst of drug concentration in the plasma after oral administration of IB.

Optimization of paeonol-loaded poly(butyl-2-cyanoacrylate) nanocapsules by central composite design with response surface methodology together with the antibacterial properties

With the aim to enhance dissolution rate and bioavailability of paeonol, paeonol-loaded poly(butyl-2-cyanoacrylate) nanocapsules (Pae@PNCs) were prepared by interfacial spontaneous polymerization for the first time. Herein, a rotatable central composite design (RCCD) with three-factor five-level was applied to evaluate the optimization experiments. To the maximum percentage encapsulation efficiency (EE%) and minimum particle size (nm) of the Pae@PNCs, a quadratic polynomial model was generated to predict and evaluate the independent variables with respect to the dependent variables. RSM model goodness fitting were confirmed by the ANOVA Table (P<0.05) through variance analysis, which predicted values of EE (%) and particle size (R² and adjusted R² were close to 1, respectively) in good agreement with experimental values. By solving the regression equation and analyzing the response surface, three-dimensional model graphs and plots, the optimal result for the preparation of Pae@PNCs were found to be: pH (2.34), Poloxamer F-68 (0.80% m/v) and ethyl acetate/α-BCA ratio (16.67 v/v) for the highest EE% (73.58±2.76%) and the smallest particle size (42.06±1.20nm). The release profiles and antibacterial activity in vitro from the optimal Pae@PNCs were performed. The results indicated that it has slow and well-controlled release, and has strong antibacterial activity in vitro than paeonol. This understanding can help to predict the conditions of optimization of poly(butyl-2-cyanoacrylate) nanoparticles formation and to improve paeonol bioavailability and pharmacological properties.