{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T12:24:30Z","timestamp":1788956670694,"version":"build-2803163510"},"reference-count":44,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T00:00:00Z","timestamp":1782172800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Excellent Young Scientists Fund\u2014Hunan Provincial Natural Science Foundation of China","award":["2024JJ4043"],"award-info":[{"award-number":["2024JJ4043"]}]},{"DOI":"10.13039\/501100010083","name":"Hunan Provincial Innovation Foundation for Postgraduates","doi-asserted-by":"crossref","award":["CX202500094"],"award-info":[{"award-number":["CX202500094"]}],"id":[{"id":"10.13039\/501100010083","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Aiming to develop high-performance flexible electrode materials for dielectric elastomer actuation systems applied to micro-crawling robots, this study proposes multi-dimensional filler composite electrode materials with a methyl vinyl silicone rubber matrix. Three types of conductive fillers\u2014namely, zero-dimensional super-conductive carbon black, one-dimensional single-walled carbon nanotubes, and two-dimensional flaky micron-sized silver powder\u2014were employed to construct a hierarchical multi-dimensional conductive network within the silicone rubber matrix via a three-stage fabrication strategy. The electrical conductivity and conductive stability of the as-prepared composite electrode materials were systematically investigated, where the intrinsic mechanisms and evolutionary laws of material electrical performance variations were analyzed. Furthermore, the effects of fillers with different dimensional morphologies on the comprehensive properties of the composites at each fabrication stage were explored, and the optimal filler dosage for each component was determined. Microstructural observations of the staged conductive network formation further verified the rationality of the stage-based functional design model. The optimized composite electrode delivers an initial electrical conductivity of 1.5 \u00d7 104 S\/m, with only a 14.9% conductivity attenuation under 50% tensile strain, demonstrating excellent electromechanical stability. Moreover, a prototype micro-crawling robot was fabricated using the optimized composite electrode, achieving a maximum linear crawling speed of 8 mm\/s. These experimental results validate the feasibility and superiority of the proposed multi-dimensional filler composite strategy. This work provides a novel technical approach for the design and development of high-performance flexible electrode materials for flexible electronic and micro-robotic actuation applications.<\/jats:p>","DOI":"10.3390\/polym18131561","type":"journal-article","created":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T17:11:49Z","timestamp":1782234709000},"page":"1561","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Novel Silicone Rubber\u2013Based Multi-Dimensional Filler Composite Electrode Materials for the Dielectric Elastomer Actuation Technology of Micro-Crawling Robots"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8650-4802","authenticated-orcid":false,"given":"Yang","family":"Hong","sequence":"first","affiliation":[{"name":"College of Intelligence Science and Technology, National University of Defense Technology, Changsha 410073, China"},{"name":"National Key Laboratory of Equipment State Sensing and Smart Support, National University of Defense Technology, Changsha 410073, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yun","family":"Yang","sequence":"additional","affiliation":[{"name":"College of Intelligence Science and Technology, National University of Defense Technology, Changsha 410073, China"},{"name":"National Key Laboratory of Equipment State Sensing and Smart Support, National University of Defense Technology, Changsha 410073, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zening","family":"Lin","sequence":"additional","affiliation":[{"name":"College of Intelligence Science and Technology, National University of Defense Technology, Changsha 410073, China"},{"name":"National Key Laboratory of Equipment State Sensing and Smart Support, National University of Defense Technology, Changsha 410073, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9406-5061","authenticated-orcid":false,"given":"Tao","family":"Jiang","sequence":"additional","affiliation":[{"name":"College of Intelligence Science and Technology, National University of Defense Technology, Changsha 410073, China"},{"name":"National Key Laboratory of Equipment State Sensing and Smart Support, National University of Defense Technology, Changsha 410073, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8247-7317","authenticated-orcid":false,"given":"Zirong","family":"Luo","sequence":"additional","affiliation":[{"name":"College of Intelligence Science and Technology, National University of Defense Technology, Changsha 410073, China"},{"name":"National Key Laboratory of Equipment State Sensing and Smart Support, National University of Defense Technology, Changsha 410073, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,23]]},"reference":[{"key":"ref_1","unstructured":"Liu, J., and Liu, Y. (2022). Smart Composite Materials, Chinese Railway Press."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1186\/s10033-022-00707-2","article-title":"A Review of Smart Materials for the Boost of Soft Actuators, Soft Sensors, and Robotics Applications","volume":"35","author":"Hao","year":"2022","journal-title":"Chin. J. Mech. Eng."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"e12005","DOI":"10.1002\/smb2.12005","article-title":"Recent Advances in Twisted and Coiled Artificial Muscles and Their Applications","volume":"1","author":"Sun","year":"2025","journal-title":"SmartBot"},{"key":"ref_4","first-page":"6","article-title":"Multifield coupling constitutive theory of soft materials and its applications in soft robotics","volume":"54","author":"Rui","year":"2025","journal-title":"Sci. Sin. Phys. Mech. Astron."},{"key":"ref_5","first-page":"644","article-title":"Soft Robots for Space Applications: Actuation, Modeling and Sensing","volume":"44","author":"Yue","year":"2023","journal-title":"J. Astronaut."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2417380","DOI":"10.1002\/adma.202417380","article-title":"Leech-Inspired Amphibious Soft Robot Driven by High-Voltage Triboelectricity","volume":"37","author":"Zheng","year":"2025","journal-title":"Adv. Mater."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1329","DOI":"10.1109\/TRO.2025.3532520","article-title":"Soft Robotic Fish Actuated by Bionic Muscle With Embedded Sensing for Self-Adaptive Multiple Modes Swimming","volume":"41","author":"Wang","year":"2025","journal-title":"IEEE Trans. Robot."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"033001","DOI":"10.1088\/1361-665X\/adae6a","article-title":"The elastic frontier: Dielectric elastomer actuators in healthcare technology","volume":"34","author":"Amine","year":"2025","journal-title":"Smart Mater. Struct."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2422905","DOI":"10.1002\/adfm.202422905","article-title":"Long, Fibrous, and Tailorable Dielectric Elastomer Artificial Muscles via Mask-Free Stamping of Carbon Nanotube Electrodes","volume":"35","author":"Shao","year":"2025","journal-title":"Adv. Funct. Mater."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"eadp4256","DOI":"10.1126\/scirobotics.adp4256","article-title":"Acrobatics at the insect scale: A durable, precise, and agile micro\u2013aerial robot","volume":"10","author":"Kim","year":"2025","journal-title":"Sci. Robot."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"eadu4474","DOI":"10.1126\/sciadv.adu4474","article-title":"Hybrid locomotion at the insect scale: Combined flying and jumping for enhanced efficiency and versatility","volume":"11","author":"Hsiao","year":"2025","journal-title":"Sci. Adv."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"0105","DOI":"10.34133\/cbsystems.0105","article-title":"Integrated Actuation and Sensing: Toward Intelligent Soft Robots","volume":"5","author":"Zhou","year":"2024","journal-title":"Cyborg Bionic Syst."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1038\/s41563-024-02035-3","article-title":"Antagonistic-contracting high-power photo-oscillators for multifunctional actuations","volume":"24","author":"Zhao","year":"2024","journal-title":"Nat. Mater."},{"key":"ref_14","first-page":"517","article-title":"Research on Output Characteristics of a Circular Dielectric Elastomer Generator","volume":"45","author":"Zhang","year":"2024","journal-title":"Power Gener. Technol."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"104875","DOI":"10.1016\/j.jmps.2022.104875","article-title":"On Maxwell stress and its relationship with the dielectric constant in the actuation of ionic polymer metal composites","volume":"164","author":"Boldini","year":"2022","journal-title":"J. Mech. Phys. Solids"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"458","DOI":"10.1002\/smll.200901162","article-title":"Flexible, transparent, conducting films of randomly stacked graphene from surfactant-stabilized, oxide-free graphene dispersions","volume":"6","author":"De","year":"2010","journal-title":"Small"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"2100953","DOI":"10.1002\/adem.202100953","article-title":"Dielectric Elastomer Actuators with Biphasic Ag\u2013EGaIn Electrodes","volume":"24","author":"Majidi","year":"2022","journal-title":"Adv. Eng. Mater."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1016\/j.snb.2018.01.145","article-title":"Stretchable composite monolayer electrodes for low voltage dielectric elastomer actuators","volume":"261","author":"Ji","year":"2018","journal-title":"Sens. Actuators B Chem."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"281","DOI":"10.1007\/s00339-012-7402-8","article-title":"Flexible and stretchable electrodes for dielectric elastomer actuators","volume":"110","author":"Rosset","year":"2012","journal-title":"Appl. Phys. A"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"43434","DOI":"10.1021\/acsomega.4c10966","article-title":"AgNW\/Graphene Hybrid Electrode for Dielectric Elastomer Actuator","volume":"10","author":"Shahsa","year":"2025","journal-title":"ACS Omega"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"1226","DOI":"10.1021\/acsnano.3c12210","article-title":"Superstretchable Liquid-Metal Electrodes for Dielectric Elastomer Transducers and Flexible Circuits","volume":"18","author":"Zang","year":"2024","journal-title":"ACS Nano"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Ma, G., Wu, X., Chen, L., Tong, X., and Zhao, W. (2020). Characterization and Optimization of Elastomeric Electrodes for Dielectric Elastomer Artificial Muscles. Materials, 13.","DOI":"10.3390\/ma13235542"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"20606","DOI":"10.1039\/D4TA01960A","article-title":"Flexible electrode materials for emerging electronics: Materials, fabrication and applications","volume":"12","author":"Liu","year":"2024","journal-title":"J. Mater. Chem. A"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"012003","DOI":"10.1088\/2631-7990\/ae02ca","article-title":"Nano\/micro-engineered metallic flexible electrodes: Advancing the era of epidermal electronics","volume":"8","author":"Zhu","year":"2026","journal-title":"Int. J. Extrem. Manuf."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"056107","DOI":"10.1063\/1.2930813","article-title":"GaInSn usage in the research laboratory","volume":"79","author":"Morley","year":"2008","journal-title":"Rev. Sci. Instrum."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"e2211202","DOI":"10.1002\/adma.202211202","article-title":"Green Flexible Electronics: Natural Materials, Fabrication, and Applications","volume":"35","author":"Hui","year":"2023","journal-title":"Adv. Mater."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"115264","DOI":"10.1016\/j.sna.2024.115264","article-title":"Paper-based microfluidic chip for sweat volume, ECG and EMG monitoring","volume":"371","author":"Yang","year":"2024","journal-title":"Sens. Actuators A Phys."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Alex, M., Khan, K.R.B., Al-Othman, A., Al-Sayah, M.H., and Al Nashash, H. (2024). MXene-Based Flexible Electrodes for Electrophysiological Monitoring. Sensors, 24.","DOI":"10.3390\/s24113260"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"128055","DOI":"10.1016\/j.colsurfa.2021.128055","article-title":"Construction of sensitive strain sensing nanofibrous membrane with polydopamine-modified MXene\/CNT dual conductive network","volume":"635","author":"Chen","year":"2022","journal-title":"Colloids Surf. A Physicochem. Eng. Asp."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"e05829","DOI":"10.1002\/advs.202505829","article-title":"Healable Dielectric Elastomer Actuator With Premature Breakdown Warning Function for Information Transmission Encryption and Human-Machine Interaction","volume":"12","author":"Liu","year":"2025","journal-title":"Adv. Sci."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Sommer-Larsen, P., and Larsen, A. (2004). Materials for Dielectric Elastomer Actuators, SPIE.","DOI":"10.1117\/12.539500"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"141","DOI":"10.1016\/j.sna.2019.06.001","article-title":"Fabrication of a flexible capacitor sensor with surface-fabric-structured conductive silicon rubber","volume":"295","author":"Gao","year":"2019","journal-title":"Sens. Actuators A Phys."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"158","DOI":"10.1016\/j.jmst.2015.12.009","article-title":"Fabrication of Flexible Transparent Conductive Films with Silver Nanowire by Vacuum Filtration and PET Mold Transfer","volume":"32","author":"Xu","year":"2016","journal-title":"J. Mater. Sci. Technol."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"228525","DOI":"10.1016\/j.jpowsour.2020.228525","article-title":"3-D printed gradient porous composite electrodes improve anodic current distribution and performance in thermally regenerative flow battery for low-grade waste heat recovery","volume":"473","author":"Shi","year":"2020","journal-title":"J. Power Sources"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"111882","DOI":"10.1016\/j.matdes.2023.111882","article-title":"High-performance ionic polymer actuators with Triple-layered multifunctional electrodes","volume":"229","author":"Zhao","year":"2023","journal-title":"Mater. Des."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1176","DOI":"10.1038\/s41928-024-01250-9","article-title":"A wearable in-sensor computing platform based on stretchable organic electrochemical transistors","volume":"7","author":"Liu","year":"2024","journal-title":"Nat. Electron."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"664","DOI":"10.1002\/adma.201003398","article-title":"Highly Flexible Silver Nanowire Electrodes for Shape-Memory Polymer Light-Emitting Diodes","volume":"23","author":"Yu","year":"2011","journal-title":"Adv. Mater."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"2204565","DOI":"10.1002\/adfm.202204565","article-title":"Super Stretchable, Self-Healing, Adhesive Ionic Conductive Hydrogels Based on Tailor-Made Ionic Liquid for High-Performance Strain Sensors","volume":"32","author":"Yao","year":"2022","journal-title":"Adv. Funct. Mater."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"112482","DOI":"10.1016\/j.colsurfb.2022.112482","article-title":"Preparation of PAA\/PAM\/MXene\/TA hydrogel with antioxidant, healable ability as strain sensor","volume":"214","author":"Qin","year":"2022","journal-title":"Colloids Surf. B Biointerfaces"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"e2109904","DOI":"10.1002\/adma.202109904","article-title":"Ultra-High Electrical Conductivity in Filler-Free Polymeric Hydrogels Toward Thermoelectrics and Electromagnetic Interference Shielding","volume":"34","author":"Wang","year":"2022","journal-title":"Adv. Mater."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"2209324","DOI":"10.1002\/adma.202209324","article-title":"Engineering Electrodes with Robust Conducting Hydrogel Coating for Neural Recording and Modulation","volume":"35","author":"Zhang","year":"2022","journal-title":"Adv. Mater."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"10886","DOI":"10.1021\/acsami.2c00513","article-title":"Highly Conductive and Mechanically Robust Cellulose Nanocomposite Hydrogels with Antifreezing and Antidehydration Performances for Flexible Humidity Sensors","volume":"14","author":"Yu","year":"2022","journal-title":"ACS Appl. Mater. Interfaces"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"2000173","DOI":"10.1002\/aisy.202000173","article-title":"Rapid Fabrication Method for Soft Devices Using Off-the-Shelf Conductive and Dielectric Acrylic Elastomers","volume":"3","author":"Kanno","year":"2020","journal-title":"Adv. Intell. Syst."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"eaaz6451","DOI":"10.1126\/scirobotics.aaz6451","article-title":"An autonomous untethered fast soft robotic insect driven by low-voltage dielectric elastomer actuators","volume":"4","author":"Ji","year":"2019","journal-title":"Sci. Robot."}],"container-title":["Polymers"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4360\/18\/13\/1561\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,27]],"date-time":"2026-06-27T04:56:19Z","timestamp":1782536179000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4360\/18\/13\/1561"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,23]]},"references-count":44,"journal-issue":{"issue":"13","published-online":{"date-parts":[[2026,7]]}},"alternative-id":["polym18131561"],"URL":"https:\/\/doi.org\/10.3390\/polym18131561","relation":{},"ISSN":["2073-4360"],"issn-type":[{"value":"2073-4360","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,23]]}}}