Synthesis of a New Type of Star-Shaped Poly(2-alkyl-2-oxazolines) on the Basis of Sulfochlorinated Calix[8]arene

Abstract

A new approach to the synthesis of sulfonyl chloride initiators with the calixarene core for the cationic polymerization of 2-oxazolines is developed. The kinetics of 2-ethyl-2-oxazoline polymerization with the synthesized octafunctional initiator at 100°С in sulfolane is studied. It is shown that the decelerated initiation of polymerization is observed in the system and the rate constant of chain propagation is kp = 1.20 × 10–3 L/(mol s). Using the cationic ring-opening polymerization of 2-alkyl-2-oxazolines initiated by calix[8]arene functionalized by sulfonyl chloride groups in the lower rim, star-shaped thermosensitive polymers are synthesized, and the molecular weight characteristics of the polymers are investigated. The critical micelle concentration of star-shaped poly(2-isopropyl-2-oxazoline) is determined (СCMC = 6.25 × 10–5 g/mL), and the solubilizability of the synthesized polymers is investigated using hydrophobic dye curcumin as an example.