TY - GEN A1 - Schmidt, Christian A1 - Behl, Marc A1 - Lendlein, Andreas A1 - Bauermann, Sabine T1 - Synthesis of high molecular weight polyglycolide in supercritical carbon dioxide N2 - Polyglycolide (PGA) is a biodegradable polymer with multiple applications in the medical sector. Here the synthesis of high molecular weight polyglycolide by ring-opening polymerization of diglycolide is reported. For the first time stabilizer free supercritical carbon dioxide (scCO2) was used as a reaction medium. scCO2 allowed for a reduction in reaction temperature compared to conventional processes. Together with the lowering of monomer concentration and consequently reduced heat generation compared to bulk reactions thermal decomposition of the product occurring already during polymerization is strongly reduced. The reaction temperatures and pressures were varied between 120 and 150 °C and 145 to 1400 bar. Tin(II) ethyl hexanoate and 1-dodecanol were used as catalyst and initiator, respectively. The highest number average molecular weight of 31 200 g mol−1 was obtained in 5 hours from polymerization at 120 °C and 530 bar. In all cases the products were obtained as a dry white powder. Remarkably, independent of molecular weight the melting temperatures were always at (219 ± 2) °C. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 284 Y1 - 2014 UR - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/9943 UR - https://nbn-resolving.org/urn:nbn:de:kobv:517-opus4-99439 ER -