%0 journal article
%@ 0032-3861
%A Peng, X., Behl, M., Zhang, P., Mazurek-Budzynska, M., Razzaq, M.Y., Lendlein, A.

%D 2016
%J Polymer

%P 318-326 
%R doi:10.1016/j.polymer.2016.10.033
%T Hexyl-modified morpholine-2,5-dione-based oligodepsipeptides with relatively low glass transition temperature
%U https://doi.org/10.1016/j.polymer.2016.10.033
 
%X Oligodepsipeptides (oDPs), alternating copolymers of an α-amino acid and an α-hydroxy acid, are typically created by ring-opening polymerization (ROP) of morpholine-2,5-dione derivatives (MDs). In general, oDPs exhibit relatively high glass transition temperatures (Tgs) caused by the strong intermolecular H-bonding between amide and ester bonds. So far, it was not reported that variation at α-amino acid moieties in MDs monomers lead to lower Tg. Here we explored whether the thermal properties of the oDPs can be adjusted by introducing a hexyl side chain in the α-hydroxy acid part of the MDs. By synthesizing a MD with an atactic pendant hexyl group at position 3, the influence of a modification at position 6 compared to a modification at position 3 towards ROP was investigated. In both cases the atactic bulky side groups hindered the H-bonding between chain segments resulting in a significant reduction of the Tgs to a temperature around human body temperature (32 and 36 °C) in contrast to ROP of a MD providing a methyl group at position 3 and a Tg ≈ 65 °C. Such oDPs could be interesting candidate materials for biomedical applications such as degradable implants.