{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T11:02:22Z","timestamp":1768734142060,"version":"3.49.0"},"reference-count":45,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,8,3]],"date-time":"2022-08-03T00:00:00Z","timestamp":1659484800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003593","name":"Brazilian National Council for Scientific and Technological Development (CNPq)","doi-asserted-by":"publisher","award":["308567\/2018-8"],"award-info":[{"award-number":["308567\/2018-8"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003593","name":"Brazilian National Council for Scientific and Technological Development (CNPq)","doi-asserted-by":"publisher","award":["305814\/2021-4"],"award-info":[{"award-number":["305814\/2021-4"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003593","name":"Brazilian National Council for Scientific and Technological Development (CNPq)","doi-asserted-by":"publisher","award":["PID2020-119047RB-I00"],"award-info":[{"award-number":["PID2020-119047RB-I00"]}],"id":[{"id":"10.13039\/501100003593","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003329","name":"Spanish Ministerio de Econom\u00eda e Innovaci\u00f3n","doi-asserted-by":"publisher","award":["308567\/2018-8"],"award-info":[{"award-number":["308567\/2018-8"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003329","name":"Spanish Ministerio de Econom\u00eda e Innovaci\u00f3n","doi-asserted-by":"publisher","award":["305814\/2021-4"],"award-info":[{"award-number":["305814\/2021-4"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003329","name":"Spanish Ministerio de Econom\u00eda e Innovaci\u00f3n","doi-asserted-by":"publisher","award":["PID2020-119047RB-I00"],"award-info":[{"award-number":["PID2020-119047RB-I00"]}],"id":[{"id":"10.13039\/501100003329","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Polymers"],"abstract":"<jats:p>Thermoplastic polyurethanes (TPUs) are versatile polymers presenting a broad range of properties as a result of their countless combination of raw materials\u2014in essence, isocyanates, polyols, and chain extenders. This study highlights the effect of two different chain extenders and their combination on the structure\u2013property relationships of TPUs synthesized by reactive extrusion. The TPUs were obtained from 4,4-diphenylmethane diisocyanate (MDI), polyester diols, and the chain extenders 1,4-butanediol (BDO) and dipropylene glycol (DPG). The BDO\/DPG ratios studied were 100\/0, 75\/25, 50\/50, 25\/75, and 0\/100 wt.%. The TPUs were characterized by size exclusion chromatography (SEC), Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), small-angle X-ray scattering (SAXS), UV\u2013vis spectroscopy, and physical-mechanical properties. The results indicate that DPG promotes compatibility between rigid (HS) and flexible (SS) segments of TPUs. Consequently, increasing DPG content (&gt;75 wt.%) reduced the organization of the rigid segments and the degree of phase separation, increasing the polydispersity of the interdomain distance and the transparency in the UV\u2013visible spectrum of the TPUs. Furthermore, increasing DPG content also reduced the amount of hydrogen bonds present in the rigid phase, reducing or extinguishing its glass transition temperature (TgHS) and melting temperature (Tm), and increasing the glass transition temperature of the flexible phase (TgSS). Therefore, increasing DPG content leads to a deterioration in mechanical properties and hydrolysis resistance.<\/jats:p>","DOI":"10.3390\/polym14153164","type":"journal-article","created":{"date-parts":[[2022,8,3]],"date-time":"2022-08-03T23:33:01Z","timestamp":1659569581000},"page":"3164","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Tuning Thermal, Morphological, and Physicochemical Properties of Thermoplastic Polyurethanes (TPUs) by the 1,4-Butanediol (BDO)\/Dipropylene Glycol (DPG) Ratio"],"prefix":"10.3390","volume":"14","author":[{"given":"Juliano R.","family":"Ernzen","sequence":"first","affiliation":[{"name":"Mantoflex Poliuretanos, Caxias do Sul 95045175, Brazil"},{"name":"Chemical Engineering Department, University of Caxias do Sul, Caxias do Sul 95070560, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0255-6654","authenticated-orcid":false,"given":"Carlos H.","family":"Romoaldo","sequence":"additional","affiliation":[{"name":"Chemical Engineering Department, University of Caxias do Sul, Caxias do Sul 95070560, Brazil"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7598-1788","authenticated-orcid":false,"given":"Cedric","family":"Gommes","sequence":"additional","affiliation":[{"name":"Department of Chemical Engineering, University of Li\u00e8ge, B6C, All\u00e9e du Six Ao\u00fbt 3, B-4000 Li\u00e8ge, Belgium"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0790-5801","authenticated-orcid":false,"given":"Jos\u00e9 A.","family":"Covas","sequence":"additional","affiliation":[{"name":"Institute for Polymers and Composites (IPC), University of Minho, Campus de Azur\u00e9m, 4800-058 Guimar\u00e3es, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9004-9868","authenticated-orcid":false,"given":"Angel","family":"Marcos-Fern\u00e1ndez","sequence":"additional","affiliation":[{"name":"Elastomers Group, Institute of Polymer Science and Technology (ICTP-CSIC), Juan de la Cierva, 3, 28006 Madrid, Spain"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2964-8508","authenticated-orcid":false,"given":"Rudinei","family":"Fiorio","sequence":"additional","affiliation":[{"name":"Faculty of Science and Engineering, Maastricht University, 6200 MD Geleen, The Netherlands"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7493-8163","authenticated-orcid":false,"given":"Ot\u00e1vio","family":"Bianchi","sequence":"additional","affiliation":[{"name":"Chemical Engineering Department, University of Caxias do Sul, Caxias do Sul 95070560, Brazil"},{"name":"Department of Materials Engineering (DEMAT), Federal University of Rio Grande do Sul (UFRGS), Porto Alegre 90040040, Brazil"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,3]]},"reference":[{"key":"ref_1","unstructured":"Oertel, G.A. 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