TY - JOUR

T1 - Temperature-responsive star-shaped poly(2-ethyl-2-oxazoline) and poly(2-isopropyl-2-oxazoline) with central thiacalix[4]arene fragments

T2 - structure and properties in solutions

AU - Lezov, A. A.

AU - Gubarev, A. S.

AU - Podsevalnikova, A. N.

AU - Senchukova, A. S.

AU - Lebedeva, E. V.

AU - Dudkina, M. M.

AU - Tenkovtsev, A. V.

AU - Nekrasova, T. N.

AU - Andreeva, L. N.

AU - Smyslov, R. Yu.

AU - Gorshkova, Yu. E.

AU - Kopitsa, G. P.

AU - Rǎdulescu, A.

AU - Pipich, V.

AU - Tsvetkov, N. V.

PY - 2019/2/7

Y1 - 2019/2/7

N2 - Temperature-responsive star-shaped poly(2-ethyl-2-oxazoline) (star-PETOX) and poly(2-isopropyl-2-oxazoline) (star-PIPOX) with arms grafted to the lower rim of thiacalix[4]arene were studied in solutions by viscometry, sedimentation velocity, light scattering, and small-angle neutron scattering. The experiments were carried out in water and tetrahydrofuran solutions. It was revealed that in tetrahydrofuran, the studied polymers were present only as individual molecules, while in aqueous solutions, in addition to individual molecules, large polymer aggregates were found. Molecular characteristics of the star-PETOX and star-PIPOX samples were estimated; their behavior in tetrahydrofuran and water was studied over a wide temperature range. It was established that a cloud point of the aqueous solution of star-PETOX (67 °C) is higher than that of a solution of star-PIPOX (35 °C). Comparison of the data obtained by dynamic light scattering and small-angle neutron scattering turned out to be fruitful in revealing all the structural levels of the organization of star-PETOX and star-PIPOX in aqueous solutions. They include the level of the individual macromolecules and the level of supramolecular organization with a star-like architecture. [Figure not available: see fulltext.]

AB - Temperature-responsive star-shaped poly(2-ethyl-2-oxazoline) (star-PETOX) and poly(2-isopropyl-2-oxazoline) (star-PIPOX) with arms grafted to the lower rim of thiacalix[4]arene were studied in solutions by viscometry, sedimentation velocity, light scattering, and small-angle neutron scattering. The experiments were carried out in water and tetrahydrofuran solutions. It was revealed that in tetrahydrofuran, the studied polymers were present only as individual molecules, while in aqueous solutions, in addition to individual molecules, large polymer aggregates were found. Molecular characteristics of the star-PETOX and star-PIPOX samples were estimated; their behavior in tetrahydrofuran and water was studied over a wide temperature range. It was established that a cloud point of the aqueous solution of star-PETOX (67 °C) is higher than that of a solution of star-PIPOX (35 °C). Comparison of the data obtained by dynamic light scattering and small-angle neutron scattering turned out to be fruitful in revealing all the structural levels of the organization of star-PETOX and star-PIPOX in aqueous solutions. They include the level of the individual macromolecules and the level of supramolecular organization with a star-like architecture. [Figure not available: see fulltext.]

KW - DLS AUC

KW - Molecular properties

KW - SANS

KW - Star-shaped polyoxazolines

KW - Thiacalix[4]arene

KW - POLYMERS

KW - MACROMOLECULES

KW - POLY(2-OXAZOLINE)S

KW - CRYSTAL-STRUCTURES

KW - 2-ALKYL-2-OXAZOLINE

KW - PEG

KW - DLSAUC

KW - INITIATORS

KW - ANGLE NEUTRON-SCATTERING

UR - http://www.scopus.com/inward/record.url?scp=85059843345&partnerID=8YFLogxK

UR - http://www.mendeley.com/research/temperatureresponsive-starshaped-poly2ethyl2oxazoline-poly2isopropyl2oxazoline-central-thiacalix4are

U2 - 10.1007/s00396-018-4458-9

DO - 10.1007/s00396-018-4458-9

M3 - Article

AN - SCOPUS:85059843345

VL - 297

SP - 285

EP - 296

JO - Colloid and Polymer Science

JF - Colloid and Polymer Science

SN - 0303-402X

IS - 2

ER -