Microstructures of capped ethylene oxide oligomers in water and n-hexane
Abstract
This report documents microstructural features of CH3(CH2-O-CH2)mCH3 dissolved in water and n-hexane for m = 11, 21, and 31. Probability densities for end-to-end distance, and the associated potential-of-mean-force (pmf), are more revealing of chain microstructures than are the corresponding results for the radii of gyration. For water, the pmf identifies three distinct regions: loop-closure, globule, and high-extension regions. The globule region affirms a water-swollen chain, and is not evident in the n-hexane results. Chain C-atom density profiles from the chain centroid are also different in the water and n-hexane cases. For n-hexane (but not water), the density profiles are similar for the different chain lengths when the distances are scaled by the observed <Rg^2>^{1/2}. For water (but not n-hexane) and the smaller chains considered, the carbon material exhibits a distinctive enhanced concentration, or internal condensation, at the centroid core of the structure.
Keywords
Cite
@article{arxiv.1208.0349,
title = {Microstructures of capped ethylene oxide oligomers in water and n-hexane},
author = {Mangesh I. Chaudhari and Lawrence R. Pratt},
journal= {arXiv preprint arXiv:1208.0349},
year = {2012}
}
Comments
8 pages, 7 figures Revision of introduction for proceedings contribution: Oil Spill Remediation: Colloid Chemistry-Based Principles and Solutions, edited by Ponisseril Somasundaran, Raymond Farinato, Partha Patra, and Kyriakos Papadopoulos