{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T04:49:53Z","timestamp":1791521393957,"version":"4.3.4"},"reference-count":30,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T00:00:00Z","timestamp":1790726400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["U23B2080"],"award-info":[{"award-number":["U23B2080"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"award":["U23B2080"],"award-info":[{"award-number":["U23B2080"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002858","name":"China Postdoctoral Science Foundation","doi-asserted-by":"publisher","award":["2023M742766"],"award-info":[{"award-number":["2023M742766"]}],"id":[{"id":"10.13039\/501100002858","id-type":"DOI","asserted-by":"publisher"}]},{"award":["2023M742766"],"award-info":[{"award-number":["2023M742766"]}],"id":[{"id":"https:\/\/ror.org\/0426zh255","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013317","name":"Shanxi Provincial Key Research and Development Project","doi-asserted-by":"publisher","award":["2024GX-YBXM-520"],"award-info":[{"award-number":["2024GX-YBXM-520"]}],"id":[{"id":"10.13039\/501100013317","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Smart Grid-National Science and Technology Major Project \u201cDemonstration of Flexible Mul-ti-terminal Interconnection for Megacity Power Grid\u201d","award":["2024ZD0802600"],"award-info":[{"award-number":["2024ZD0802600"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nanomaterials"],"abstract":"<jats:p>Identifying the molecular origins of thermal and electric-field response can guide polyimide insulation design. We combined an 18-film aromatic imide oligomer ensemble, reactive molecular dynamics, and signed finite-field r2SCAN-3c calculations to separate packing, chain-end chemistry, and directional electronic response. Independently initialized films exhibited a fivefold variation in probe-accessible volume, with distinct connected void geometries at similar accessible fractions. Across sixteen 5 ps thermal trajectories, terminal imide N\u2013H sites accounted for 20 of 21 persistent reference-bond losses; the nonterminal inventory contained 14 new C\u2013O connectivities and one C\u2013N loss. In six matched film pairs, nonterminal records increased from 2 to 5 at 1600 K and from 12 to 19 at 1800 K between 5 and 10 ps, revealing the growing contribution of nonterminal rearrangement. Trajectories extending to 20 ps also resolved the onset of increased mass escape. At \u00b12 V nm\u22121, the isolated ether-linked bis-imide fragment showed 0.342\u20130.841 eV frontier-gap narrowing across six directions, compared with at most 0.049 eV for the imide fragment, despite overlapping size-normalized induced responses. Together, these results identify chain termination and segment orientation as candidate design variables and provide quantitative descriptors for morphology-matched thermal comparisons and orientation-resolved electronic screening.<\/jats:p>","DOI":"10.3390\/nano16191236","type":"journal-article","created":{"date-parts":[[2026,9,30]],"date-time":"2026-09-30T14:19:37Z","timestamp":1790777977000},"page":"1236","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Chain-End Reactivity and Anisotropic Electronic Softening Define Candidate Design Targets in BPDA\/4,4\u2032-ODA Polyimide Insulation"],"prefix":"10.3390","volume":"16","author":[{"given":"Dongqiao","family":"Bai","sequence":"first","affiliation":[{"name":"Xihang University, Xi\u2019an 710077, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tianyu","family":"Lin","sequence":"additional","affiliation":[{"name":"China State Key Laboratory of Electric Insulation and Power Equipment, Xi\u2019an Jiaotong University, Xi\u2019an 710049, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1109\/TDEI.2010.5411997","article-title":"Dielectric Breakdown of Polyimide Films: Area, Thickness and Temperature Dependence","volume":"17","author":"Diaham","year":"2010","journal-title":"IEEE Trans. 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