{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T15:45:54Z","timestamp":1787240754384,"version":"build-2736575974"},"reference-count":27,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,5,18]],"date-time":"2021-05-18T00:00:00Z","timestamp":1621296000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100015622","name":"Ministerul Cercet\u0103rii \u015fi Inov\u0103rii","doi-asserted-by":"publisher","award":["2N\/2019"],"award-info":[{"award-number":["2N\/2019"]}],"id":[{"id":"10.13039\/501100015622","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>The present paper is focused on evaluating the most suitable dispersion method in the epoxy matrix of two self-healing systems containing dicyclopentadiene (DCPD) and 5-ethylidene-2-norbornene (ENB) monomers encapsulated in a urea-formaldehyde (UF) shell, prior to integration, fabrication and impact testing of specimens. Both microstructural analysis and three-point bending tests were performed to evaluate and assess the optimum dispersion method. It was found that ultrasonication damages the microcapsules of both healing systems, thus magnetic stirring was used for the dispersion of both healing systems in the epoxy matrix. Using magnetic dispersion, 5%, 7%, 10%, 12% and 15% volumes of microcapsules were embedded in glass fibre composites. Some of the samples were subjected to thermal cycling between \u221220 \u00b0C and +100 \u00b0C for 8 h, to evaluate the behaviour of both healing systems after temperature variation. Impact test results showed that the mechanical behaviour decreases with increasing microcapsule volume, while for specimens subjected to thermal cycling, the impact strength increases with microcapsule volume up to 10%, after which a severe drop in impact strength follows. Retesting after 48 h shows a major drop in mechanical properties in specimens containing 15% MUF-ENB microcapsules, up to total penetration of the specimen.<\/jats:p>","DOI":"10.3390\/polym13101642","type":"journal-article","created":{"date-parts":[[2021,5,18]],"date-time":"2021-05-18T23:34:46Z","timestamp":1621380886000},"page":"1642","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Evaluation of Dispersion Methods and Mechanical Behaviour of Glass Fibre Composites with Embedded Self-Healing Systems"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6598-6307","authenticated-orcid":false,"given":"Ionut Sebastian","family":"Vintila","sequence":"first","affiliation":[{"name":"National Research and Development Institute for Gas Turbines COMOTI, 061126 Bucharest, Romania"},{"name":"Advanced Polymer Materials Group, University Politehnica of Bucharest, 011061 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sorin","family":"Draghici","sequence":"additional","affiliation":[{"name":"Laboratory for Advanced Testing and Mechanical Characterization of Materials, Department of Strength of Materials, Faculty of Industrial Engineering and Robotics, University Politehnica of Bucharest, 060042 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Horia Alexandru","family":"Petrescu","sequence":"additional","affiliation":[{"name":"Laboratory for Advanced Testing and Mechanical Characterization of Materials, Department of Strength of Materials, Faculty of Industrial Engineering and Robotics, University Politehnica of Bucharest, 060042 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandru","family":"Paraschiv","sequence":"additional","affiliation":[{"name":"National Research and Development Institute for Gas Turbines COMOTI, 061126 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1768-4491","authenticated-orcid":false,"given":"Mihaela Raluca","family":"Condruz","sequence":"additional","affiliation":[{"name":"National Research and Development Institute for Gas Turbines COMOTI, 061126 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6792-4425","authenticated-orcid":false,"given":"Lucia Raluca","family":"Maier","sequence":"additional","affiliation":[{"name":"National Research and Development Institute for Gas Turbines COMOTI, 061126 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4501-4062","authenticated-orcid":false,"given":"Adela","family":"Bara","sequence":"additional","affiliation":[{"name":"National Institute for Research and Development in Electrical Engineering ICPE-CA Bucharest, 030138 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Madalina","family":"Necolau","sequence":"additional","affiliation":[{"name":"Advanced Polymer Materials Group, University Politehnica of Bucharest, 011061 Bucharest, Romania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1016\/j.jmrt.2014.10.016","article-title":"Self-healing epoxy composites: Preparation, characterization and healing performance","volume":"4","author":"Chowdhury","year":"2015","journal-title":"J. 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