{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T19:44:06Z","timestamp":1792093446716,"version":"4.4.0"},"reference-count":37,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2022,11,6]],"date-time":"2022-11-06T00:00:00Z","timestamp":1667692800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Research Foundation of Korea","award":["NRF-2020R1A4A2002854"],"award-info":[{"award-number":["NRF-2020R1A4A2002854"]}]},{"name":"National Research Foundation of Korea","award":["KCCUS20220001"],"award-info":[{"award-number":["KCCUS20220001"]}]},{"name":"Korea CCUS Association","award":["NRF-2020R1A4A2002854"],"award-info":[{"award-number":["NRF-2020R1A4A2002854"]}]},{"name":"Korea CCUS Association","award":["KCCUS20220001"],"award-info":[{"award-number":["KCCUS20220001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Fire in energy storage systems, such as lithium-ion batteries, has been raised as a serious concern due to the difficulty of suppressing it. Fluorine-based non-flammable agents used as internal substances leaked through the fine pores of the polymer outer shell, leading to a degradation of fire extinguishing performance. To improve the durability of the fire suppression microcapsules and the stability of the ouster shell, a complex coacervation was used, which could be microencapsulated at a lower temperature, and the polymer shell was coated with urea-formaldehyde (UF) resin. The outermost UF resin formed elaborate bonds with the gelatin-based shell, and thus, the structure of the outer shell became denser, thereby improving the loss resistance of the inner substance and thermal stability. The double-layered microcapsules had an average particle diameter of about 309 \u03bcm, and a stable outer shell formed with a mass loss of 0.005% during long-term storage for 100 days. This study confirmed that the double-layered microcapsules significantly improved thermal stability, resistance to core material loss, core material content and fire suppression performance compared to single wall microcapsules. These results indicated that the double-layered structure was suitable for the production of microcapsules for initial fire suppression, including highly volatile non-flammable agents with a low boiling point.<\/jats:p>","DOI":"10.3390\/ma15217831","type":"journal-article","created":{"date-parts":[[2022,11,7]],"date-time":"2022-11-07T03:02:22Z","timestamp":1667790142000},"page":"7831","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":29,"title":["Double-Layered Polymer Microcapsule Containing Non-Flammable Agent for Initial Fire Suppression"],"prefix":"10.3390","volume":"15","author":[{"given":"Dong Hun","family":"Lee","sequence":"first","affiliation":[{"name":"Department of Chemical Engineering, Konkuk University, Gwangjin-gu, Seoul 05029, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Soonhyun","family":"Kwon","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Konkuk University, Gwangjin-gu, Seoul 05029, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Young Eun","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Konkuk University, Gwangjin-gu, Seoul 05029, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Na Yeon","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Konkuk University, Gwangjin-gu, Seoul 05029, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ji Bong","family":"Joo","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, Konkuk University, Gwangjin-gu, Seoul 05029, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Leventon, I.T., McGrattan, K.B., Davis, R.D., Hamburger, K., and Melly, N. 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