{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,1]],"date-time":"2026-04-01T13:50:54Z","timestamp":1775051454755,"version":"3.50.1"},"reference-count":51,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2019,11,17]],"date-time":"2019-11-17T00:00:00Z","timestamp":1573948800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Biodegradable polyesters gain significant attention because of their wide potential biomedical applications. The ring-opening polymerization method is widely used to obtain such polymers, due to high yields and advantageous properties of the obtained material. The preparation of new, effective, and bio-safe catalytic systems for the synthesis of biomedical polymers is one of the main directions of the research in modern medical chemistry. The new diethylzinc\/propyl gallate catalytic system was first used in the copolymerization of \u03b5-caprolactone and rac-lactide. In this paper, the activity of the new zinc-based catalytic system in the copolymerization of cyclic esters depending on the reaction conditions was described. The microstructure analysis of the obtained copolyesters and their toxicity studies were performed. Resulted copolyesters were characterized by low toxicity, moderate dispersity (1.19\u20131.71), varying randomness degree (0.18\u20130.83), and average molar mass (5300\u20139800 Da).<\/jats:p>","DOI":"10.3390\/molecules24224168","type":"journal-article","created":{"date-parts":[[2019,11,18]],"date-time":"2019-11-18T04:31:10Z","timestamp":1574051470000},"page":"4168","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Application of Diethylzinc\/Propyl Gallate Catalytic System for Ring-Opening Copolymerization of rac-Lactide and \u03b5-Caprolactone"],"prefix":"10.3390","volume":"24","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7062-886X","authenticated-orcid":false,"given":"Rafa\u0142","family":"Wyr\u0119biak","sequence":"first","affiliation":[{"name":"Department of Biomaterials Chemistry, Chair of Analytical Chemistry and Biomaterials, Faculty of Pharmacy, Medical University of Warsaw, 1 Banacha St., Warsaw 02-097, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ewa","family":"Oledzka","sequence":"additional","affiliation":[{"name":"Department of Biomaterials Chemistry, Chair of Analytical Chemistry and Biomaterials, Faculty of Pharmacy, Medical University of Warsaw, 1 Banacha St., Warsaw 02-097, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ramona","family":"Figat","sequence":"additional","affiliation":[{"name":"Department of Environmental Health Sciences, Faculty of Pharmacy, Medical University of Warsaw, 1 Banacha St., Warsaw 02-097, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marcin","family":"Sobczak","sequence":"additional","affiliation":[{"name":"Department of Biomaterials Chemistry, Chair of Analytical Chemistry and Biomaterials, Faculty of Pharmacy, Medical University of Warsaw, 1 Banacha St., Warsaw 02-097, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,17]]},"reference":[{"key":"ref_1","first-page":"865","article-title":"Application of the lithium and magnesium initiators for the synthesis of glycolide, lactide, and epsilon-caprolactone copolymers biocompatible with brain tissue","volume":"79","author":"Kasperczyk","year":"2006","journal-title":"J. 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