The synthesis of the ABA triblock copolymers, comprising MeOx as block A and BuOx or BuOzi, respectively as block B, was conducted via cationic ring opening polymerization with sequential monomer addition to achieve a block-like polymer architecture as reported previously. Detailed information about the synthesis and polymer analysis can be found elsewhere and in the Supporting Information (Figure -S4, Table -S4). After synthesis, the polymers were analyzed using 1 H NMR spectroscopy and SEC and their glass transition temperatures (Tg) were obtained from DSC measurements (Table ). H-NMR analysis shows the presence of all repeat units, and end group analysis gives a molar mass in reasonable agreement with the expected values. The molar mass values obtained from SEC are significantly different from the expected values, which can be attributed to the PMMA calibration standard. The low dispersity clearly suggests a highly living character of the polymerization. In contrast PVP and P(VP-co-VA) show a much higher dispersity as expected for a radical polymerization. Both, pMeOx-pBuOzi-pMeOx (P1) and pMeOx-pBuOx-pMeOx (P2) revealed a single Tg at 50 °C (P1) and 61 °C (P2), respectively. The relatively low Tg compared to PVP K17 (138 °C) and P(VP-co-VA) (103 °C) is potentially beneficial for excipients for hot melt extrusion, in particular for the formulation of heat sensitive drugs (e.g. indomethacin), as the processing temperature can be lowered to prevent possible degradation of the drug.