An isotopic effect in self-assembly of amphiphilic block copolymers: The role of hydrogen bonds

Rina Shvartzman-Cohen, Chun Lai Ren, Igal Szleifer*, Rachel Yerushalmi-Rozen

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

12 Scopus citations

Abstract

An isotopic effect was observed in solutions of self-assembling (SA) amphiphilic block copolymers: it was found that the micellization enthalpy, temperature and the size of the formed micelles are affected by replacing H 2O by D2O. The SA of solvated block-copolymers (poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide)) in H 2O, D2O and their mixtures was investigated as a function of temperature. High sensitivity differential scanning calorimetry revealed that the micellization temperature is reduced, and the enthalpic penalty of the transition and size of the formed micelles increase when H2O is exchanged by D2O. Molecular theory calculations suggest that the difference in the hydrogen bond strength of the solvent, H2O or D2O, is the origin of the different structural and conformational properties of the solvated block copolymers. The differences in the solvent properties were predicted to modify the solubility and consequently the SA of the polymers in the two solvents, as experimentally measured. The study provides an insight into the role of hydrogen bonding in systems of amphiphilic block copolymers, and suggests that in SA polymers small differences in hydrogen-bonding strength of the solvent may result in observable macroscopic effects.

Original languageEnglish (US)
Pages (from-to)5003-5011
Number of pages9
JournalSoft Matter
Volume5
Issue number24
DOIs
StatePublished - Dec 16 2009

ASJC Scopus subject areas

  • Chemistry(all)
  • Condensed Matter Physics

Fingerprint Dive into the research topics of 'An isotopic effect in self-assembly of amphiphilic block copolymers: The role of hydrogen bonds'. Together they form a unique fingerprint.

Cite this