TY - JOUR A1 - Kricheldorf, H. R. A1 - Weidner, Steffen A1 - Scheliga, F. T1 - Ring-Expansion Polymerization of 𝝐-Caprolactone, Glycolide, and l-lactide with a Spirocyclic Tin(IV) Catalyst Derived from or 2,2′-Dihydroxy-1,1′-Binaphthyl – New Results and a Revision T2 - Macromolecular Chemistry and Physics N2 - In contrast to other cyclic tin bisphenoxides, polymerizations of glycolide and l-lactide with the spirocyclic tin(IV) bis-1,1′-bisnapthoxide yield linear chains having a 1,1′-bisnapthol end group and no cycles. In the case of l-lactide, LA/Cat ratio and temperature are varied and at 160 °C or below, all polylactides mainly consist of even-numbered chains. A total predominance of even-numbered chains is also found for homopolymerization of glycolide, or the copolymerization of glycolide and l-lactide, when conducted <120 °C. Linear chains having a bisnaphthol end group are again the main reaction products of ring-expansion polymerizations (REP) of 𝝐-caprolactone, but above 150 °C cycles are also formed. PB - Wiley VCH GmbH KW - Polylactide KW - MALDI-TOF MS KW - Polymerization PY - 2021 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/54193 AN - OPUS4-54193 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-541931 VL - 222 IS - 24 SP - 1 EP - 10 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany