{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T01:17:02Z","timestamp":1788225422987,"version":"build-2803163510"},"reference-count":51,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T00:00:00Z","timestamp":1788134400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Science and Technology Project of State Grid Corporation of China","award":["52243725000L"],"award-info":[{"award-number":["52243725000L"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Epoxy resins are widely used in electronic packaging and electrical insulation, but their permanent cross-linked networks and low intrinsic thermal conductivity restrict material recycling and heat dissipation. In this work, a recyclable epoxy composite was developed by combining a dual-dynamic epoxy network with silica-coated poly(p-phenylene benzobisoxazole) fibers. The composite architecture integrates thermally activated network rearrangement, amine-induced matrix degradation, electrically insulating fibrous heat transport, and recovery of the reinforcing phase within a single material system. The silica-containing coating modified the PBO-fiber surface morphology and fiber\/matrix interphase, while increasing fiber content produced a progressive increase in thermal conductivity. At a fiber content of 12 wt%, the composite exhibited a thermal conductivity of 0.267 W\/(m\u00b7K), together with low dielectric loss and a balance among thermal, dielectric, and mechanical properties. After hot-press reprocessing, the composite retained 92.1% of its original thermal conductivity. Immersion in n-hexylamine resulted in macroscopic disintegration of the epoxy matrix, enabling recovery of PBO@SiO2 fibers that retained their overall morphology and surface Si distribution. These results establish the composition\u2013property relationships of a recyclable, thermally conductive, and electrically insulating fiber-reinforced epoxy composite. This work provides a feasible strategy for designing recyclable epoxy composites with balanced thermal conductivity, dielectric reliability, and fiber recoverability.<\/jats:p>","DOI":"10.3390\/polym18172118","type":"journal-article","created":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T01:05:26Z","timestamp":1788224726000},"page":"2118","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Study of Dielectric and Thermal Conductivity Properties of Recyclable Epoxy Resin Reinforced with SiO2-Coated Poly(p-phenylene benzobisoxazole) Fibers"],"prefix":"10.3390","volume":"18","author":[{"given":"Xiangyu","family":"Zhao","sequence":"first","affiliation":[{"name":"Electric Power Research Institute, State Grid Heilongjiang Electric Power Company Limited, Harbin 150030, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]},{"given":"Difei","family":"Wang","sequence":"additional","affiliation":[{"name":"Electric Power Research Institute, State Grid Heilongjiang Electric Power Company Limited, Harbin 150030, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"}]},{"given":"Xueting","family":"Wang","sequence":"additional","affiliation":[{"name":"Electric Power Research Institute, State Grid Heilongjiang Electric Power Company Limited, Harbin 150030, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"software","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"given":"Xiaohui","family":"He","sequence":"additional","affiliation":[{"name":"Electric Power Research Institute, State Grid Heilongjiang Electric Power Company Limited, Harbin 150030, China"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"investigation","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"102855","DOI":"10.1016\/j.xcrp.2025.102855","article-title":"Toward Sustainable Thermosets: Advances in Toughening and Degradation Strategies for Epoxy Resins","volume":"6","author":"He","year":"2025","journal-title":"Cell Rep. 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