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Lithium ion conducting polymerized ionic liquid pentablock terpolymers as solid-state electrolytes
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Ionic liquids as a novel class of electrolytes in polymeric aqueous biphasic systems
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Quantum-dot doped polymeric scintillation material for radiation detection
In this study, scintillation and luminescence enhancement were observed in a Quantum Dot-doped scintillating polymer, facilitating energy transfer with polymer medium and scintillating dye. 2,5-diphenyloxazole (PPO) and Cadmium Sulfide (CdS) Quantum Dots (QD) with 418 nm emission coated with oleic acid were dispersed in a polyvinyl toluene (PVT) matrix with transparency retained. Under UV excitation a sharp emission was detected at 426 nm from minimal QD loading with possible indication of QD energy transfer. Scintillation enhancement was observed with different radioactive sources in PVT-PPO/QD polymer with a photomultiplier detector setup. The response to gamma and beta radiation was investigated with differences in the energy spectrum and a count increase observed with increased QD loading.
The synthesis of molecular recognition polymer particles via miniemulsion polymerization
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Glass-fiber-reinforced polymeric film as an efficient protecting layer for stable Li metal electrodes
With numerous reports on protecting films for stable lithium (Li) metal electrodes, the key attributes for how to construct these efficient layers have rarely been fully investigated. Here, we report a rationally designed hybrid protective layer (HPL) with each component aligning with one key attribute; i.e., cross-linked poly(dimethylsiloxane) (PDMS) enhances flexibility, polyethylene glycol (PEG) provides homogeneous ion-conducting channels, and glass fiber (GF) affords mechanical robustness. A significant improvement of the electrochemical performance of HPL-modified electrodes can be achieved in Li/HPL@Cu half cells, HPL@Li/HPL@Li symmetric cells, and HPL@Li/LiFePO 4 full cells. Even with an industrial standard LiFePO 4 cathode (96.8 wt % active material), the assembled cell still exhibits a capacity retention of 90% after 100 cycles at 1 C. More importantly, the functionality of each component has been studied comprehensively via electrochemical and physical experiments and simulations, which will provide useful guidance on how to construct efficient protective layers for next-generation energy storage devices.
Multimodal Chemical Imaging for Linking Adhesion with Local Chemistry in Agrochemical Multicomponent Polymeric Coatings
Seed coatings improve germination and offer higher crop yields through a blend of active ingredients (such as insecticides and fungicides), polymers, waxes, fillers, and pigments. To reach their full potential, fundamental formulation challenges bridging structure and function need to be addressed. In some instances, during industrial-volume packing and transportation, coated seeds do not flow well through elevators, conveyers, and applicators, which may reduce yield and add cost. In this work, we illustrate a combinatorial chemical imaging approach to study seed coatings at the microscale to link chemical and physical properties responsible for low seed flowability. The local chemical composition was examined using time-of-flight secondary ion mass spectrometry (ToF-SIMS) and at comparable length scales, the local adhesive properties were examined using atomic force microscopy (AFM) force volume mapping. The link between the chemical and the adhesive properties was established by non-negative matrix factorization (NMF). The correlative multimodal imaging approach developed here utilizing AFM force volume mapping, ToF-SIMS chemical mapping, and data analytics offers a path for linking function with localized chemistry when investigating multicomponent soft material systems.
Building Semipermeable Films One Monomer at a Time: Structural Advantages via Molecular Layer Deposition vs Interfacial Polymerization
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Preparation of Ordered Polyacetylene by Solid-State Polymerization in Nanoscale Confinement
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Molecular Simulations to Elucidate Transport Phenomena in Polymeric Membranes
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MIL-101(Cr) Polymeric Fiber Adsorbents for Sub-Ambient Post-Combustion CO 2 Capture
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A Quantum-Based Approach to Predict Primary Radiation Damage in Polymeric Networks
Initial atomistic-level radiation damage in chemically reactive materials is thought to induce reaction cascades that can result in undesirable degradation of macroscale properties. Ensembles of quantum-based molecular dynamics (QMD) simulations can accurately predict these cascades, but extracting chemical insights from the many underlying trajectories is a labor-intensive process that can require substantial a priori intuition. We develop here a general and automated graph-based approach to extract all chemically distinct structures sampled in QMD simulations and apply our approach to predict primary radiation damage of polydimethylsiloxane (PDMS), the main constituent of silicones. A postprocessing protocol is developed to identify underlying polymer backbone structures as connected components in QMD trajectories. Furthermore, these backbones form a repository of radiation-damaged structures. A scheme for extracting and updating a library of isomorphically distinct structures is proposed to identify the spanning set and aid chemical interpretation of the repository. The analyses are applied to ensembles of cascade QMD simulations in which the four element types in PDMS are selectively excited in primary knock-on atom events. Our approach reveals a much higher degree of combinatorial complexity in this system than was inferred through radiolysis experiments. Probabilities are extracted for radiation-induced network changes including formation of branch points, carbon linkages, cycles, bond scissions, and carbon uptake into the Si–O siloxane backbone network. The general analysis framework presented here is readily extendable to modeling chemical degradation of other polymers and molecular materials and provides a basis for future quantum-informed multiscale modeling of radiation damage.