{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T17:35:50Z","timestamp":1790876150647,"version":"4.1.0"},"reference-count":22,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,2,19]],"date-time":"2025-02-19T00:00:00Z","timestamp":1739923200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Deutsche Forschungsgemeinschaft","award":["GRK2430"],"award-info":[{"award-number":["GRK2430"]}]},{"name":"Deutsche Forschungsgemeinschaft","award":["380321452"],"award-info":[{"award-number":["380321452"]}]},{"DOI":"10.13039\/501100001659","name":"Interactive Fiber Rubber Composites","doi-asserted-by":"publisher","award":["GRK2430"],"award-info":[{"award-number":["GRK2430"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001659","name":"Interactive Fiber Rubber Composites","doi-asserted-by":"publisher","award":["380321452"],"award-info":[{"award-number":["380321452"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>In this study, we investigated the influence of an epoxy end-capped polypropylene oxide crosslinker (epoxy-PPO) on the formation of the crosslinked network structure, the stress\u2013strain response, and the electro-mechanical actuation performance of a maleic anhydride functionalized liquid isoprene rubber (LIR). The crosslinker amount varied from 10 (C-LIR-10) to 50 (C-LIR-50) weight parts per hundred parts (phr) of LIR. The swelling test of the cured rubbers revealed that C-LIR-20 formed the densest crosslinked network with the lowest chloroform uptake value within this series. The crosslinked rubber became stiffer in tensile response upon increasing the epoxy-PPO amount from C-LIR-10 to C-LIR-20 and then softened at higher amounts. The SEM measurements were used to relate this composition-induced softening of the rubbers to the phase morphology evolution from nanoscale homogeneity in C-LIR-10 to microscale segregations of excess crosslinkers in C-LIR-50. The use of epoxy-PPO improved the dielectric constant value of LIR; however, the leakage current through the films also increased from 25 \u00b5A DC to 320 \u00b5A DC for LIR-30 and LIR-50, respectively, during DEA operation. The electro-mechanical actuation tests with circular actuators showed that the C-LIR-10 elastomer film demonstrated a radial strain of 1.7% on activation at an electric field strength of 17.5 V\/\u00b5m. At higher crosslinker amounts, the close proximity of excess epoxy-PPO molecules caused leakage current across elastomer films thus diminishing the actuation strain of otherwise relatively softer elastomers with higher dielectric constant values.<\/jats:p>","DOI":"10.3390\/polym17040551","type":"journal-article","created":{"date-parts":[[2025,2,19]],"date-time":"2025-02-19T09:36:22Z","timestamp":1739957782000},"page":"551","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Effects of Polymeric Crosslinker on Network Structure, Morphology, and Properties of Liquid Isoprene Rubber"],"prefix":"10.3390","volume":"17","author":[{"given":"Jishnu","family":"Nirmala Suresh","sequence":"first","affiliation":[{"name":"Institute of Materials Science, Faculty of Mechanical Science and Engineering, TUD Dresden University of Technology, 01062 Dresden, Germany"},{"name":"Department of Elastomers, Leibniz-Institut f\u00fcr Polymerforschung Dresden e.V., 01069 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-6954-5367","authenticated-orcid":false,"given":"Hans","family":"Liebscher","sequence":"additional","affiliation":[{"name":"Institute of Solid-State Electronics, Faculty of Electrical and Computer Engineering, TUD Dresden University of Technology, 01062 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6176-6737","authenticated-orcid":false,"given":"Hartmut","family":"Komber","sequence":"additional","affiliation":[{"name":"Center Macromolecular Structure Analysis, Leibniz-Institut f\u00fcr Polymerforschung Dresden e.V., 01069 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Muhammad","family":"Tahir","sequence":"additional","affiliation":[{"name":"Department of Elastomers, Leibniz-Institut f\u00fcr Polymerforschung Dresden e.V., 01069 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7062-9598","authenticated-orcid":false,"given":"Gerald","family":"Gerlach","sequence":"additional","affiliation":[{"name":"Institute of Solid-State Electronics, Faculty of Electrical and Computer Engineering, TUD Dresden University of Technology, 01062 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0967-4557","authenticated-orcid":false,"given":"Sven","family":"Wie\u00dfner","sequence":"additional","affiliation":[{"name":"Institute of Materials Science, Faculty of Mechanical Science and Engineering, TUD Dresden University of Technology, 01062 Dresden, Germany"},{"name":"Department of Elastomers, Leibniz-Institut f\u00fcr Polymerforschung Dresden e.V., 01069 Dresden, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"20160026","DOI":"10.1098\/rsfs.2016.0026","article-title":"Electroactive polymers for sensing","volume":"6","author":"Wang","year":"2016","journal-title":"Interface Focus"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"822","DOI":"10.2514\/2.3902","article-title":"Electroactive Polymers as Artificial Muscles: A Review","volume":"39","year":"2002","journal-title":"J. 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C"}],"container-title":["Polymers"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-4360\/17\/4\/551\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T16:38:04Z","timestamp":1760027884000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-4360\/17\/4\/551"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,2,19]]},"references-count":22,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2025,2]]}},"alternative-id":["polym17040551"],"URL":"https:\/\/doi.org\/10.3390\/polym17040551","relation":{},"ISSN":["2073-4360"],"issn-type":[{"value":"2073-4360","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,2,19]]}}}