biostudies-literatureUnknown11(5)Weidner SMCyclic polylactides were prepared in bulk at 170 °C, crystallized at 120 °C and then annealed at temperatures between 130 and 170 °C with variation of catalyst, catalyst concentration and annealing time. The transformation of the initially formed low melting (L<i>T</i> _m) crystallites, having melting temperatures (<i>T</i> _m) < 180 °C into high melting (H<i>T</i> _m) crystallites having <i>T</i> _m values > 189 °C was monitored by means of DSC measurements and characterized in selected cases by SAXS measurements. It was confirmed that the formation of H<i>T</i> _m crystallites involves a significant growth of the thickness of the lamellar crystallites along with smoothing of their surface. Annealing at 170 °C for 1 d or longer causes therRSC advances2872-2883https://www.ebi.ac.uk/biostudies/studies/S-EPMC8693987biostudies-literatureAbout the transformation of low <i>T</i> _m into high <i>T</i> _m poly(l-lactide)s by annealing under the influence of transesterification catalysts.PMC8693987Weidner SMChatti SKricheldorf HRMeyer AfalseAbout the transformation of low <i>T</i> _m into high <i>T</i> _m poly(l-lactide)s by annealing under the influence of transesterification catalysts.Cyclic polylactides were prepared in bulk at 170 °C, crystallized at 120 °C and then annealed at temperatures between 130 and 170 °C with variation of catalyst, catalyst concentration and annealing time. The transformation of the initially formed low melting (L<i>T</i> _m) crystallites, having melting temperatures (<i>T</i> _m) < 180 °C into high melting (H<i>T</i> _m) crystallites having <i>T</i> _m values > 189 °C was monitored by means of DSC measurements and characterized in selected cases by SAXS measurements. It was confirmed that the formation of H<i>T</i> _m crystallites involves a significant growth of the thickness of the lamellar crystallites along with smoothing of their surface. Annealing at 170 °C for 1 d or longer causes ther2021-01-01T00:00:00Z2021 Jan2025-04-25T22:54:26.818Z2025-04-06T09:14:35.425ZS-EPMC86939873542424010.1039/d0ra10012a