{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,25]],"date-time":"2026-09-25T06:31:35Z","timestamp":1790317895360,"version":"4.1.0"},"reference-count":34,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2018,4,3]],"date-time":"2018-04-03T00:00:00Z","timestamp":1522713600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Economy and Competitiveness (MINECO) of Spain","award":["MAT2014-52644-R"],"award-info":[{"award-number":["MAT2014-52644-R"]}]},{"name":"Ministry of Economy and Competitiveness (MINECO) of Spain","award":["MAT2017-87204-R"],"award-info":[{"award-number":["MAT2017-87204-R"]}]},{"name":"DGAPA-PAPIIT-UNAM of Mexico","award":["IN-103516"],"award-info":[{"award-number":["IN-103516"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Polymers used in the biomedical sector can be exposed to ionizing radiation (X-ray, gamma) in vivo as implants or ex vivo for sterilization purposes (gamma, electron beam). This ionizing radiation can, at certain levels, cause degradation of the polymer. Polycaprolactones (PCL) of different molecular weights were irradiated with electron beam and the changes in their chemical structure and physical properties with the dose were evaluated. Electron beam irradiation produced crosslinking and chain scission in the PCL chain without significant predominance of one mechanism over the other. Minimum dose for gelation decreased with the increase in PCL molecular weight whereas crosslinking efficiency was almost independent of PCL molecular weight. Carboxylic groups, hydroxyl groups and new saturated hydrocarbon species were detected by proton nuclear magnetic resonance (NMR). These species were consistent with a mechanism where chain scission could take place at any bond in the PCL chain with preference in the \u2013COO\u2013CH2\u2013 bond. Crosslinking decreased significantly the crystallization temperature of PCL. Tensile properties decreased continuously with the increase in dose. Irradiation with gamma rays produced a faster decay in mechanical properties than electron beam.<\/jats:p>","DOI":"10.3390\/polym10040397","type":"journal-article","created":{"date-parts":[[2018,4,3]],"date-time":"2018-04-03T13:31:51Z","timestamp":1522762311000},"page":"397","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":43,"title":["Effect of Ionizing Radiation on the Chemical Structure and the Physical Properties of Polycaprolactones of Different Molecular Weight"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6592-9871","authenticated-orcid":false,"given":"Rodrigo","family":"Navarro","sequence":"first","affiliation":[{"name":"Instituto de Ciencia y Tecnolog\u00eda de Pol\u00edmeros (CSIC), Juan de la Cierva 3, 28006 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guillermina","family":"Burillo","sequence":"additional","affiliation":[{"name":"Instituto de Ciencias Nucleares, Universidad Nacional Aut\u00f3noma de M\u00e9xico, Circuito Exterior, Ciudad Universitaria, 04510 Ciudad de M\u00e9xico, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Esbaide","family":"Adem","sequence":"additional","affiliation":[{"name":"Instituto de F\u00edsica, Universidad Nacional Aut\u00f3noma de M\u00e9xico, Circuito Exterior, Ciudad Universitaria, 04510 Ciudad de M\u00e9xico, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Angel","family":"Marcos-Fern\u00e1ndez","sequence":"additional","affiliation":[{"name":"Instituto de Ciencia y Tecnolog\u00eda de Pol\u00edmeros (CSIC), Juan de la Cierva 3, 28006 Madrid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,4,3]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1217","DOI":"10.1016\/j.progpolymsci.2010.04.002","article-title":"The return of a forgotten polymer\u2014Polycaprolactone in the 21st century","volume":"35","author":"Woodruff","year":"2010","journal-title":"Prog. 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