{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T06:15:40Z","timestamp":1775196940658,"version":"3.50.1"},"reference-count":39,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,3,28]],"date-time":"2026-03-28T00:00:00Z","timestamp":1774656000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004488","name":"Croatian Science Foundation","doi-asserted-by":"crossref","award":["IP-2020-02-4344"],"award-info":[{"award-number":["IP-2020-02-4344"]}],"id":[{"id":"10.13039\/501100004488","id-type":"DOI","asserted-by":"crossref"}]},{"name":"European Union\u2019s Horizon Europe Research and Innovation Programme","award":["EURO-LABS-RAPID-2023-1"],"award-info":[{"award-number":["EURO-LABS-RAPID-2023-1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Calcium carbonate is a widely used filler in polymer composites due to its low cost and ability to improve stiffness, dimensional stability, and impact resistance. However, its hydrophilic surface limits compatibility with nonpolar polymer matrices, making surface modification essential to improve filler dispersion and interfacial adhesion. Stearic acid is commonly applied as a surface modifier for calcium carbonate because it readily chemisorbs onto the mineral surface and forms densely packed self-assembled monolayers that improve hydrophobic character. Despite its widespread use, stearic acid exhibits limited thermal and interfacial stability under polymer processing conditions, motivating the development of stabilization strategies. In this work, gamma and electron-beam irradiation were applied to stearic-acid-modified calcium carbonate to modify the surface-bound stearic acid layer with the aim of enhancing its interfacial stability, surface resistance, and hydrophobic performance, and to evaluate the influence of irradiation atmosphere on these effects. The modified materials were characterized in terms of structural integrity, surface wettability, surface free energy, thermal stability, and optical properties. The results demonstrate that ionizing radiation enhances surface hydrophobicity and coating durability while preserving the crystal structure of the CaCO3 substrate. Gamma irradiation of stearic-acid-modified vaterite exhibited strong atmosphere dependence, with improved hydrophobicity under oxygen-free conditions, whereas electron-beam irradiation showed more robust and oxygen-insensitive behavior. Based on the observed improvements in hydrophobicity, surface free energy, and thermal stability, electron-beam irradiation emerges as a promising and less atmosphere-sensitive approach for producing durable stearic-acid-modified CaCO3 fillers suitable for polymer composite applications.<\/jats:p>","DOI":"10.3390\/polym18070831","type":"journal-article","created":{"date-parts":[[2026,3,30]],"date-time":"2026-03-30T13:41:53Z","timestamp":1774878113000},"page":"831","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Atmosphere-Dependent Radiation Stabilization of Stearic Acid on Vaterite CaCO3: A Comparison of Gamma and Electron-Beam Irradiation"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-5496-5102","authenticated-orcid":false,"given":"Helena","family":"Biljani\u0107","sequence":"first","affiliation":[{"name":"Laboratory for Precipitation Processes, Division of Materials Chemistry, Ru\u0111er Bo\u0161kovi\u0107 Institute, Bijeni\u010dka Cesta 54, 10 000 Zagreb, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2221-4176","authenticated-orcid":false,"given":"Urszula","family":"Gryczka","sequence":"additional","affiliation":[{"name":"Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warszaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5115-6334","authenticated-orcid":false,"given":"Marta","family":"Walo","sequence":"additional","affiliation":[{"name":"Institute of Nuclear Chemistry and Technology, Dorodna 16, 03-195 Warszaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4152-4893","authenticated-orcid":false,"given":"Damir","family":"Kralj","sequence":"additional","affiliation":[{"name":"Laboratory for Precipitation Processes, Division of Materials Chemistry, Ru\u0111er Bo\u0161kovi\u0107 Institute, Bijeni\u010dka Cesta 54, 10 000 Zagreb, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5981-8590","authenticated-orcid":false,"given":"Katarina","family":"Maru\u0161i\u0107","sequence":"additional","affiliation":[{"name":"Laboratory for Precipitation Processes, Division of Materials Chemistry, Ru\u0111er Bo\u0161kovi\u0107 Institute, Bijeni\u010dka Cesta 54, 10 000 Zagreb, Croatia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"457","DOI":"10.1007\/s13205-021-02995-2","article-title":"Calcium Carbonate Nano- and Microparticles: Synthesis Methods and Biological Applications","volume":"11","author":"Fadia","year":"2021","journal-title":"3 Biotech"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"827","DOI":"10.1016\/j.polymer.2004.11.111","article-title":"Filler Toughening of Plastics. 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