Synthesis of Star-Shaped Polymers Based on 2-ALKYL-2-Oxazoline with a Calix[8]Arene Central Core and the Study of Their Heat-Sensitive Properties

This work describes the synthesis of thermosensitive eight-point star-shaped polymers with a central core comprised of residual octa-ester-tert-butylcalix[8]arene with oligo-2-ethyl-2-oxazoline-block-2-isopropyl-2-oxazoline rays. It is found that, despite the presence of two blocks with substantially different temperatures of the coil – globule transition, block copolymers exhibit only one lower critical solution temperature (LCST), and the phase transition is observed at a temperature close to the transition temperature of the homopolymer with a lower LCST. For the first time it is found that, upon incubating for some time in an aqueous solution above the LCST, star polymers with temperature-sensitive polyoxazoline rays self-assemble to form nanofibers and structures with more complex morphology.