A high-response-frequency bimodal network polyacrylate elastomer with ultrahigh power density under low electric field.

Dielectric elastomers, used as driver modules, require high power density to enable fast movement and efficient work of soft robots. Polyacrylate elastomers usually suffer from low power density under low electric fields due to limited response frequency. Here, we propose a bimodal network polyacrylate dielectric elastomer which breaks the intrinsic coupling relationship between dielectric and mechanical properties, featuring relatively high dielectric constant, low Young's modulus, and wide driving frequency bandwidth (~200 Hz) like silicones.

Atomic-Level Matching Metal-Ion Organic Hybrid Interface to Enhance Energy Storage of Polymer-Based Composite Dielectrics.

In this work, a distinctive "metal-ion organic hybrid interface" (MOHI) between polyimide (PI) and calcium niobate (CNO) nanosheets is designed. The metal ions in the MOHI can achieve atomic-level matching not only with the inorganic CNO, but also with the PI chains, forming uniform and strong chemical bonds. These results are demonstrated by experiment and theory calculations.

High-Temperature Polymer Dielectrics Designed Using an Invertible Molecular Graph Generative Model.

Generating new molecules with the desired physical or chemical properties is the key challenge of computational material design. Deep learning techniques are being actively applied in the field of data-driven material informatics and provide a promising way to accelerate the discovery of innovative materials. In this work, we utilize an invertible graph generative model to generate hypothetical promising high-temperature polymer dielectrics.

A Bilayer High-Temperature Dielectric Film with Superior Breakdown Strength and Energy Storage Density.

The further electrification of various fields in production and daily life makes it a topic worthy of exploration to improve the performance of capacitors for a long time, including thin-film capacitors. The discharge energy density of thin-film capacitors that serves as one of the important types directly depends on electric field strength and the dielectric constant of the insulation material. However, it has long been a great challenge to improve the breakdown strength and dielectric constant simultaneously.

Core-Shell Engineering of Conductive Fillers toward Enhanced Dielectric Properties: A Universal Polarization Mechanism in Polymer Conductor Composites.

Flexible dielectric and electronic materials with high dielectric constant (k) and low loss are constantly pursued. Encapsulation of conductive fillers with insulating shells represents a promising approach, and has attracted substantial research efforts. However, progress is greatly impeded due to the lack of a fundamental understanding of the polarization mechanism.

Suppressing the Loss of Polymer-Based Dielectrics for High Power Energy Storage.

Polymer-based dielectrics have received intensive interest from academic community in the field of high-power energy storage owing to their superior flexibility and fast charge-discharge ability. Recently, how to suppress the loss of polymer-based dielectrics has been increasingly recognized as a critical point to attain a high charge-discharge efficiency in the film capacitors. Some achievements are made in analyzing the source of loss and suppressing loss via Edison's trial and error method.

Recent Progress and Future Prospects on All-Organic Polymer Dielectrics for Energy Storage Capacitors.

With the development of advanced electronic devices and electric power systems, polymer-based dielectric film capacitors with high energy storage capability have become particularly important. Compared with polymer nanocomposites with widespread attention, all-organic polymers are fundamental and have been proven to be more effective choices in the process of scalable, continuous, and large-scale industrial production, leading to many dielectric and energy storage applications. In the past decade, efforts have intensified in this field with great progress in newly discovered dielectric polymers, fundamental production technologies, and extension toward emerging computational strategies.

Development and Validation of a Novel Risk Prediction Model Using Recursive Feature Elimination Algorithm for Acute-on-Chronic Liver Failure in Chronic Hepatitis B Patients With Severe Acute Exacerbation.

Patients with chronic hepatitis B (CHB) with severe acute exacerbation (SAE) are at a progression stage of acute-on-chronic liver failure (ACLF) but uniform models for predicting ACLF occurrence are lacking. We aimed to present a risk prediction model to early identify the patients at a high risk of ACLF and predict the survival of the patient. We selected the best variable combination using a novel recursive feature elimination algorithm to develop and validate a classification regression model and also an online application on a cloud server from the training cohort with a total of 342 patients with CHB with SAE and two external cohorts with a sample size of 96 and 65 patients, respectively.

Soft, tough, and fast polyacrylate dielectric elastomer for non-magnetic motor.

Dielectric elastomer actuators (DEAs) with large electrically-actuated strain can build light-weight and flexible non-magnetic motors. However, dielectric elastomers commonly used in the field of soft actuation suffer from high stiffness, low strength, and high driving field, severely limiting the DEA's actuating performance. Here we design a new polyacrylate dielectric elastomer with optimized crosslinking network by rationally employing the difunctional macromolecular crosslinking agent.

Flexible and Stretchable Capacitive Sensors with Different Microstructures.

Recently, sensors that can imitate human skin have received extensive attention. Capacitive sensors have a simple structure, low loss, no temperature drift, and other excellent properties, and can be applied in the fields of robotics, human-machine interactions, medical care, and health monitoring. Polymer matrices are commonly employed in flexible capacitive sensors because of their high flexibility.

All-Organic Dielectrics with High Breakdown Strength and Energy Storage Density for High-Power Capacitors.

Polymer-based film capacitors with high breakdown strength and excellent flexibility are crucial in the field of advanced electronic devices and electric power systems. Although massive works are carried to enhance the energy storage performances, it is still a great challenge to improve the energy density of polymer composites under the premise of large-scale industrial production. Herein, a general strategy is proposed to improve the intrinsic breakdown strength and energy storage performances by blending core-shell structured methyl methacrylate-butadiene-styrene (MBS) rubber particles into a polymer matrix.

Hypersonic force measurements using internal balance based on optical micromachined Fabry-Perot interferometry.

Force measurements using wind tunnel balance are necessary for determining a variety of aerodynamic performance parameters, while the harsh environment in hypersonic flows requires that the measurement instrument should be reliable and robust, in against strong electromagnetic interference, high vacuum, or metal (oxide) dusts. In this paper, we demonstrated a three-component internal balance for hypersonic aerodynamic force measurements, using novel optical micromachined Fabry-Perot interferometric (FPI) strain gauges as sensing elements. The FPI gauges were fabricated using Micro-Opto-Electro-Mechanical Systems (MOEMS) surface and bulk fabrication techniques.