High-Sensitivity Microcalorimetry and Gel Permeation Chromatography in Tandem Reveal the Complexity of the Synthesis of Poly-(2-isopropyl-2-oxazoline) Stars

A series of star poly(2-isopropyl-2-oxazolines) (S-PIPOZ) was prepared by two different approaches: “coupling-onto (CO)” and “core-first (CF)”. On the one hand, for “the core-first” approach, SCF-PIPOZ were prepared by direct cationic ring opening polymerization from a tetra tosylate-functionalized pentaerythrityl core. On the other hand, for the “coupling-onto” approach, SCO-PIPOZ were synthesized by coupling via copper alkyne-azide...