BROWSE

Related Researcher

Author's Photo

Park, Soojin
Nano-Functional Materials Lab
Research Interests
  • Block Copolymers, nanostructured materials for Lithium-Ion batteries, wearable and stretchable energy storage applications

ITEM VIEW & DOWNLOAD

Retention mechanism of poly(ethylene oxide) in reversed-phase and normal-phase liquid chromatography

Cited 38 times inthomson ciCited 39 times inthomson ci
Title
Retention mechanism of poly(ethylene oxide) in reversed-phase and normal-phase liquid chromatography
Author
Cho, DPark, SoojinHong, JChang, T
Keywords
Poly(ethylene oxide); Retention mechanism; Temperature effects
Issue Date
2003-02
Publisher
ELSEVIER SCIENCE BV
Citation
JOURNAL OF CHROMATOGRAPHY A, v.986, no.2, pp.191 - 198
Abstract
The retention behavior of low- and high-molecular-mass poly(ethylene oxide) (PEO) in reversed-phase (RP) and normal-phase (NP) liquid chromatography was investigated. In RPLC using a C18 bonded silica stationary phase and an acetonitrile-water mixture mobile phase, the sorption process of PEO to the stationary phase showed ΔH°>0 and ΔS°>0. Therefore, PEO retention in RPLC separation is an energetically unfavorable, entropy-driven process, which results in an increase of PEO retention as the temperature increases. In addition, at the enthalpy-entropy compensation point the elution volume of PEO was very different from the column void volume. These observations are quite different from the RPLC retention behavior of many organic polymers. The peculiar retention behavior of PEO in RPLC separation can be understood in terms of the hydrophobic interaction of this class of typical amphiphilic compounds with the non-polar stationary phase, on the one hand, and with the aqueous mobile phase, on the other. The entropy gain due to the release of the solvated water molecules from the PEO chain and the stationary phase is believed to be responsible for the entropy-driven separation process. On the other hand, in NPLC using an amino-bonded silica stationary phase and an acetonitrile-water mixture mobile phase, PEO showed normal enthalpy-driven retention behavior: ΔH°<0 and ΔS°<0, with the retention decreasing with increasing temperature and PEO eluting near the column void volume at the enthalpy-entropy compensation point. Therefore, high-resolution temperature gradient NPLC separation of high-molecular-mass PEO samples can be achieved with relative ease. The molecular mass distribution of high-molecular-mass PEO was found to be much narrower than that measured by size-exclusion chromatography.
URI
Go to Link
DOI
10.1016/S0021-9673(02)01953-2
ISSN
0021-9673
Appears in Collections:
ECHE_Journal Papers
Files in This Item:
2-s2.0-0037423106.pdf Download

find_unist can give you direct access to the published full text of this article. (UNISTARs only)

Show full item record

qrcode

  • mendeley

    citeulike

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.

MENU