Synthesis of diverse polythioimidocarbonates via ring-opening copolymerization of epoxides and isothiocyanates catalyzed by organoboron catalyst was reported *** aromatic and aliphatic isothiocyanates underwent succes...
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Synthesis of diverse polythioimidocarbonates via ring-opening copolymerization of epoxides and isothiocyanates catalyzed by organoboron catalyst was reported *** aromatic and aliphatic isothiocyanates underwent successful copolymerization with terminal and internal epoxides,allowing for the precise tuning of the performance of the resultant copolymers over a broad *** wide scope of available isothiocyanates and epoxides enables the direct construction of sulfur-containing functional polymers featuring both high glass transition temperature and refractive ***,it was observed that aromatic isothiocyanates polymerize much faster than aliphatic ones,and the reactivity difference facilitated the one-step synthesis of block polymers from mixed aromatic isothiocyanates,aliphatic isothiocyanates and epoxides due to the preferential incorporation of aromatic isothiocyanates over the aliphatic analogues during their alternating copolymerization with *** produced polythioimidocarbonates can be used as positive resists for electron beam lithography(sensitivity of 130μC/cm^(2) and contrast of 1.53 for poly(CHO-alt-EITC)).Coupling with their high refractive index(1.58—1.68),polythioimidocarbonates might find functional applications in *** results render ring-opening copolymerization of epoxides and isothiocyanates a facile route to enrich functional polymer library.
While anion exchange membrane water electrolyzers (AEMWEs) have achieved significant performance advances in recent decades, overpotentials remain high relative to their proton exchange membrane water electrolyzer (PE...
While anion exchange membrane water electrolyzers (AEMWEs) have achieved significant performance advances in recent decades, overpotentials remain high relative to their proton exchange membrane water electrolyzer (PEMWE) counterparts, requiring AEMWE-specific catalyst layer design strategies to further advance this technology. In this work, the role of the ionomer in catalyst layer structure and quality, catalyst layer stability, and ion conduction for supporting electrolyte-fed AEMWEs is assessed for catalyst layers composed of NiFeO and PiperION TP85 from Versogen at variable ionomer contents (0-30 wt %) for tests up to 200 h. The results reveal that, for supporting electrolyte-fed AEM devices, the ionomer is not required for ion conduction through the catalyst layer. Instead, the ionomer is found to play a critical role in catalyst layer structure and stability, where intermediate ionomer contents lead to the lowest overpotentials, highest effective surface areas, and lowest catalyst layer resistances. Catalyst layer stability is found to be a function of both catalyst adhesion and ionomer loss. These results show that an ionomer may be selected which is not of the same chemistry as the anion exchange membrane, mitigating ionomer stability concerns throughout the catalyst layer and offering a pathway towards highly active and stable AEMWEs.
Membrane technology has become a promising solution for a wide range of separation processes, including wastewater treatment, solvent recovery, and oil–water separation, due to its low energy consumption, cost-effect...
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A selenium-functionalizedε-caprolactone was synthesized by introducing a phenyl selenide group at the 7-position.A polymer was obtained through the ring-opening polymerization of this monomer in a base/thiourea binar...
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A selenium-functionalizedε-caprolactone was synthesized by introducing a phenyl selenide group at the 7-position.A polymer was obtained through the ring-opening polymerization of this monomer in a base/thiourea binary organocatalytic system.A living polymerization process was achieved under mild *** resulting polymers had a controlled molecular weight with a narrow molecular weight distributions and high end-group *** copolymers could be obtained by copolymerizing this monomer withε-*** thermal degradation temperature of the obtained copolymers decreased with the increasing molar ratio of selenide functionalized monomer in copolymers,while the glass transition temperature *** addition,the phenyl selenide side group could be further modified to a polyselenonium salt,which resulted in a polymer with good antibacterial *** survival rate of *** and *** was only 9%with a polymer concentration of 62.5μg/mL.
In living tissue, pain provides a localized alert to damage and elicits an adaptive response, including the ability to heal. Mimicking these abilities in soft robotics is a key challenge. Here, we design a self-healin...
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A one-dimensional model is proposed to predict the leveling of coating defects or irregularities on a planar surface. Though shear thinning rheology is the focus of this paper, any viscous non-Newtonian rheology can b...
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A one-dimensional model is proposed to predict the leveling of coating defects or irregularities on a planar surface. Though shear thinning rheology is the focus of this paper, any viscous non-Newtonian rheology can be included in the model. Surface tension, gravity and viscous forces are accounted for in the model. A novel numerical technique is presented to obtain solutions of the model. Results agree with a full two-dimensional solution of the flow held obtained with a spectral element method. A new dimensionless group is identified which indicates the significance of shear-thinning theology. Defects are made with a notched blade used to coat pigmented liquids on polymer films. The defect shapes are obtained at different times by drying under infrared. The dried surface is characterized with a stylus profilometer. The surface profiles and the final amount of leveling compare well with the model predictions. Copyright (C) 1996 Elsevier science Ltd
We provide a critical review on the recent development of flexible lithium-ion batteries(FLIBs)for flexible electronic *** innovative designs of cell configuration for bendable and stretchable FLIBs,selection of activ...
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We provide a critical review on the recent development of flexible lithium-ion batteries(FLIBs)for flexible electronic *** innovative designs of cell configuration for bendable and stretchable FLIBs,selection of active materials,and evaluation methods for FLIBs are *** grand challenges for FLIBs are energy density and scale-up fabrication as demonstrated in the ***,the lack of quantitative evaluation methods for FLIBs'performance and nondestructive tools to probe the mechanical degradation may significantly hinder the development of FLIB *** for future research directions,based on the current state of progress,are discussed.
A simple arithmetic procedure was developed in order to be able to band-ratio dichroic measurements from simple attenuated total reflection (ATR)-IR spectroscopy to measure the surface molecular orientation of any pol...
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A simple arithmetic procedure was developed in order to be able to band-ratio dichroic measurements from simple attenuated total reflection (ATR)-IR spectroscopy to measure the surface molecular orientation of any polymer showing dichroism. This development eliminates the need to get a reproducible contact area or a reference band which does not show dichroism upon drawing. This method is universally applicable to any material showing dichroic IR bands. No assumptions are made regarding the structure of the sample in order to calculate the dichroic ratio. Furthermore, no special attachments are required for the dichroic measurements.
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