Probing the Structure and Thermoresponsive Behavior of Multicompartment Micelles

However, structural rearrangements are challenging to characterize. Here, we combine solution- and solid-state NMR spectroscopy with complementary techniques (DLS, DSC, PXRD) to investigate two potentially MCM-forming copolymers: methoxy poly(ethylene glycol)-block-poly(butyl acrylate)-block-poly(N-isopropylacrylamide) (PBuAN250) and methoxy poly(ethylene glycol)-block-poly(benzyl acrylate)-block-poly(N-isopropylacrylamide) (PBzAN300).

P-fraction values were extracted from variable-temperature 1H NMR to quantify the lower critical solution temperature (LCST) transition of poly(N-isopropylacrylamide) (PNIPAM), revealing how core rigidity affects the transition. This was complemented by T2 relaxation time data to further probe dynamics of chains upon rearrangement. Nuclear Overhauser effect spectroscopy (NOESY) was used to reveal spatial proximities between different polymer blocks.