Rodolphe Obeid, E. Maltseva, A. Thünemann
Feb 18, 2009
Citations
2
Influential Citations
81
Citations
Quality indicators
Journal
Macromolecules
Abstract
Hydrophobically end-modified (HM) poly(2-ethyl-2-oxazolines) (PEtOx) and poly(2-isopropyl-2-oxazolines) (PiPrOx) bearing an n-octadecyl chain on both termini or on one chain end only were prepared by cationic ring-opening polymerization of 2-ethyl-2-oxazoline and 2-isopropyl-2-oxazoline, respectively, and subsequent end-group modification. The polymers had a molar mass (Mn) ranging from 7000 to 13 000 g mol−1, a size distribution Mw/Mn 0.97. All polymers, except the semitelechelic sample C18-PiPrOx-OH 13K (Mn = 13 000 g mol−1), formed core−shell micelles in cold water with a hydrodynamic radius (RH), measured by dynamic light scattering, between 7 and 12 nm and a core of radius (Rc), determined by analysis of small-angle X-ray scattering (SAXS) data, of ∼1.3 nm. Aqueous solutions of all polymers underwent a heat-induced phase transition detected by an increase in solution turbidity at a temperature (Tcp, cloud point) ranging from 32 to 62 °C, depending on polymer stru...