{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T04:46:50Z","timestamp":1790830010477,"version":"4.1.0"},"reference-count":32,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2022,3,24]],"date-time":"2022-03-24T00:00:00Z","timestamp":1648080000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>The cross-linking structure of the Ethylene-propylene-diene monomer (EPDM) is made up of a number of cross-linking types, including carbon atoms from the main chain or monomer and ether crosslinks formed during degradation. Through molecular dynamic simulations, the contribution of each type of cross-linked structure to the dynamics and mechanical properties of EPDM, the study\u2019s focus, were investigated. Cross-linking between the tertiary carbons of two main chains, cross-linking at the monomer\u2019s unsaturated position, ether cross-linking after oxidation, and other combinations of target cross-linked carbon atoms from different positions, totaling eight types of cross-linked types, were mixed with EPDM free chains in a 1:1 ratio to form eight types of cross-linked EPDMs. These varieties of cross-linked EPDMs were then compared to an uncross-linked EPDM in terms of density, radius of gyration, free volume, mean square displacement, and uniaxial tensile stress-strain curves. It was found that the cross-linking was always proven to have a favorable influence on mechanical characteristics; however, the relaxation inhibition effect varied. The cross-linking between the diene monomer at the C9 position resulted in a more flexible molecular shape and was more than double the free volume of the uncross-linked EPDM, resulting in an improved diffusion ability. The ether cross-linking produced by the oxidation of the side chain cross-linking improved the positive contribution to stiffness and enhanced the inhibitory impact on diffusion properties, whereas the main chain cross-linking had the opposite effect. The research presented in this study leads to a better knowledge of the microscopic aspects underlying EPDM performance.<\/jats:p>","DOI":"10.3390\/polym14071308","type":"journal-article","created":{"date-parts":[[2022,3,24]],"date-time":"2022-03-24T23:31:43Z","timestamp":1648164703000},"page":"1308","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["The Effect of Cross-Linking Type on EPDM Elastomer Dynamics and Mechanical Properties: A Molecular Dynamics Simulation Study"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5255-4449","authenticated-orcid":false,"given":"Yajian","family":"Wang","sequence":"first","affiliation":[{"name":"National Center for Materials Service Safety, University of Science and Technology Beijing (USTB), Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huifang","family":"Liu","sequence":"additional","affiliation":[{"name":"National Center for Materials Service Safety, University of Science and Technology Beijing (USTB), Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pengpeng","family":"Li","sequence":"additional","affiliation":[{"name":"National Center for Materials Service Safety, University of Science and Technology Beijing (USTB), Beijing 100083, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Linbing","family":"Wang","sequence":"additional","affiliation":[{"name":"Joint USTB Virginia Tech Lab on Multifunctional Materials, University of Science and Technology Beijing (USTB), Beijing 100083, China"},{"name":"Department Civil & Environmental Engineering, Virginia Tech, Blacksburg, VA 24061, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"152693","DOI":"10.1016\/j.jallcom.2019.152693","article-title":"Reinforcing effects of waterproof substrate on the photo-, thermal and pH stabilities of perovskite nanocrystals","volume":"817","author":"Liu","year":"2020","journal-title":"J. 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