{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T10:56:36Z","timestamp":1790592996366,"version":"4.1.0"},"reference-count":48,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T00:00:00Z","timestamp":1790553600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["RS-2025-19643007"],"award-info":[{"award-number":["RS-2025-19643007"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]},{"award":["RS-2025-19643007"],"award-info":[{"award-number":["RS-2025-19643007"]}],"id":[{"id":"https:\/\/ror.org\/013aysd81","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Conventional lead-based protective materials used in diagnostic radiology involve some notable limitations in terms of high weight, toxicity, and environmental concerns associated with their disposal. Lead-free polymer shielding materials incorporating high-atomic-number fillers and iodine-containing components have therefore attracted increasing attention. However, high filler loading can induce particle agglomeration, localized iodine-rich regions, interfacial defects, and nonuniform X-ray attenuation. Accordingly, improving filler dispersion and structural stability is essential to maintain effective shielding performance. In this study, the effects of lignin-assisted interfacial stabilization on filler dispersion, iodine retention, structural properties, and X-ray shielding performance in highly filled polyurethane (PU) composites were investigated. At 80 kVp, a 3 wt% lignin sheet exhibited a radiation protection efficiency of 77.4%, a linear attenuation coefficient of 48.52 cm\u22121, a half-value layer (HVL) of 0.143 mm, and a mean free path (MFP) of 0.206 mm. These results indicate that lignin functions as a bio-derived interfacial stabilizer rather than a primary X-ray attenuator, improving filler utilization through enhanced dispersion, packing structure, and iodine immobilization. The proposed lignin-assisted PU\/Bi2O3\/iodine composite therefore shows potential as an environmentally conscious auxiliary shielding material for diagnostic X-rays and low-dose scattered radiation.<\/jats:p>","DOI":"10.3390\/polym18192359","type":"journal-article","created":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T10:00:34Z","timestamp":1790589634000},"page":"2359","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Lignin-Assisted Dispersion and Iohexol Retention in Lead-Free Bi2O3\/Iohexol-Loaded Waterborne Polyurethane Sheets for Diagnostic X-Ray Attenuation"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6637-736X","authenticated-orcid":false,"given":"Seon-Chil","family":"Kim","sequence":"first","affiliation":[{"name":"Department of Biomedical Engineering, School of Medicine, Keimyung University, 1095 Dal-gubeol-daero, Daegu 42601, Republic of Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"418","DOI":"10.1148\/radiol.2020192256","article-title":"Patient exposure from radiologic and nuclear medicine procedures in the United States: Procedure vol-ume and effective dose for the period 2006\u20132016","volume":"295","author":"Mettler","year":"2020","journal-title":"Radiology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"021002","DOI":"10.1088\/1361-6498\/added2","article-title":"A systematic review on the occupational health impacts of ionising radiation exposure among healthcare professionals","volume":"45","author":"Lopes","year":"2025","journal-title":"J. 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