Stimuli-responsive aggregation of high molar mass poly(N,N-diethylacrylamide)-b-poly(4-acryloylmorpholine) in tetrahydrofuran

The self-assembly of block copolymers constitutes a timely research area in polymer science with implications for applications like sensing or drug-delivery. In here, we investigate the unprecedented aggregation behaviour of high molecular weight block copolymer poly(N,N-diethylacrylamide)-b-poly(4-acryloylmorpholine) (PDEA-b-PAM) (Mn>400 kg/mol) in organic solvent tetrahydrofuran (THF). To elucidate the aggregation, dynamic light scattering, cryo transmission electron microscopy and turbidimetry were employed. The aggregate formation was assigned to the unprecedented upper critical solution temperature behaviour of PAM in THF at elevated concentration (> 6 wt%) and high molar masses. Various future directions for this new thermo-responsive block copolymer are envisioned, e.g. in the areas of photonics or templating of inorganic structures.