Solution models for binary components of significantly different molecular sizes

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

As a solution theory, Raoult's law is commonly used to estimate the activities of solutes and solvents of comparable molecular sizes while the Flory-Huggins (F-H) model is used for the activities of small liquids in high polymers. For a great many systems where the solute and solvent differ only moderately in molecular size (e.g.; by 4-10 times), there has been no confirmed choice of a preferred model; examples of such systems are those of ordinary organic compounds in liquid triolein (MW = 885.4 g·mol-1) and poly(propylene glycol) (PPG) (MW = ~1,000 g·mol-1). The observed nearly athermal solubilities of many nonpolar organic solids in these solvents provide unique experimental data to examine the merit of a solution model. As found, Raoult's law underestimates widely, and the F-H model underestimates slightly, the solid solubilities in triolein and PPG because these models underestimate the solution entropy for these solute-solvent pairs. To rectify this problem, the molecular segments of a large sized liquid solvent (e.g.; triolein) are assumed to act as independent mixing units to increase the solute-solvent mixing entropy. This adjustment leads to a modified F-H model in which the "ideal" or "athermal" solubility of a solid in volume fraction, at a particular temperature, is equal to the solid's activity at that temperature. Results from other studies give further support for the modified F-H model to interpret the partition data of compounds with organic solvents.

Original languageEnglish
Pages (from-to)1438-1451
Number of pages14
JournalJournal of Solution Chemistry
Volume42
Issue number7
DOIs
Publication statusPublished - 2013 Aug 1

Fingerprint

Triolein
solutes
Raoult law
Solubility
Propylene Glycol
solubility
Entropy
propylene
glycols
Liquids
liquids
entropy
organic solids
high polymers
Temperature
organic compounds
Organic compounds
Organic solvents
partitions
Volume fraction

All Science Journal Classification (ASJC) codes

  • Biophysics
  • Biochemistry
  • Molecular Biology
  • Physical and Theoretical Chemistry

Cite this

@article{32c5868a347b4797a358b0604f32ee44,
title = "Solution models for binary components of significantly different molecular sizes",
abstract = "As a solution theory, Raoult's law is commonly used to estimate the activities of solutes and solvents of comparable molecular sizes while the Flory-Huggins (F-H) model is used for the activities of small liquids in high polymers. For a great many systems where the solute and solvent differ only moderately in molecular size (e.g.; by 4-10 times), there has been no confirmed choice of a preferred model; examples of such systems are those of ordinary organic compounds in liquid triolein (MW = 885.4 g·mol-1) and poly(propylene glycol) (PPG) (MW = ~1,000 g·mol-1). The observed nearly athermal solubilities of many nonpolar organic solids in these solvents provide unique experimental data to examine the merit of a solution model. As found, Raoult's law underestimates widely, and the F-H model underestimates slightly, the solid solubilities in triolein and PPG because these models underestimate the solution entropy for these solute-solvent pairs. To rectify this problem, the molecular segments of a large sized liquid solvent (e.g.; triolein) are assumed to act as independent mixing units to increase the solute-solvent mixing entropy. This adjustment leads to a modified F-H model in which the {"}ideal{"} or {"}athermal{"} solubility of a solid in volume fraction, at a particular temperature, is equal to the solid's activity at that temperature. Results from other studies give further support for the modified F-H model to interpret the partition data of compounds with organic solvents.",
author = "Hung, {Wei Nung} and Tsair-Fuh Lin and Chiou, {Cary T.}",
year = "2013",
month = "8",
day = "1",
doi = "10.1007/s10953-013-0041-7",
language = "English",
volume = "42",
pages = "1438--1451",
journal = "Journal of Solution Chemistry",
issn = "0095-9782",
publisher = "Springer New York",
number = "7",

}

Solution models for binary components of significantly different molecular sizes. / Hung, Wei Nung; Lin, Tsair-Fuh; Chiou, Cary T.

In: Journal of Solution Chemistry, Vol. 42, No. 7, 01.08.2013, p. 1438-1451.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Solution models for binary components of significantly different molecular sizes

AU - Hung, Wei Nung

AU - Lin, Tsair-Fuh

AU - Chiou, Cary T.

PY - 2013/8/1

Y1 - 2013/8/1

N2 - As a solution theory, Raoult's law is commonly used to estimate the activities of solutes and solvents of comparable molecular sizes while the Flory-Huggins (F-H) model is used for the activities of small liquids in high polymers. For a great many systems where the solute and solvent differ only moderately in molecular size (e.g.; by 4-10 times), there has been no confirmed choice of a preferred model; examples of such systems are those of ordinary organic compounds in liquid triolein (MW = 885.4 g·mol-1) and poly(propylene glycol) (PPG) (MW = ~1,000 g·mol-1). The observed nearly athermal solubilities of many nonpolar organic solids in these solvents provide unique experimental data to examine the merit of a solution model. As found, Raoult's law underestimates widely, and the F-H model underestimates slightly, the solid solubilities in triolein and PPG because these models underestimate the solution entropy for these solute-solvent pairs. To rectify this problem, the molecular segments of a large sized liquid solvent (e.g.; triolein) are assumed to act as independent mixing units to increase the solute-solvent mixing entropy. This adjustment leads to a modified F-H model in which the "ideal" or "athermal" solubility of a solid in volume fraction, at a particular temperature, is equal to the solid's activity at that temperature. Results from other studies give further support for the modified F-H model to interpret the partition data of compounds with organic solvents.

AB - As a solution theory, Raoult's law is commonly used to estimate the activities of solutes and solvents of comparable molecular sizes while the Flory-Huggins (F-H) model is used for the activities of small liquids in high polymers. For a great many systems where the solute and solvent differ only moderately in molecular size (e.g.; by 4-10 times), there has been no confirmed choice of a preferred model; examples of such systems are those of ordinary organic compounds in liquid triolein (MW = 885.4 g·mol-1) and poly(propylene glycol) (PPG) (MW = ~1,000 g·mol-1). The observed nearly athermal solubilities of many nonpolar organic solids in these solvents provide unique experimental data to examine the merit of a solution model. As found, Raoult's law underestimates widely, and the F-H model underestimates slightly, the solid solubilities in triolein and PPG because these models underestimate the solution entropy for these solute-solvent pairs. To rectify this problem, the molecular segments of a large sized liquid solvent (e.g.; triolein) are assumed to act as independent mixing units to increase the solute-solvent mixing entropy. This adjustment leads to a modified F-H model in which the "ideal" or "athermal" solubility of a solid in volume fraction, at a particular temperature, is equal to the solid's activity at that temperature. Results from other studies give further support for the modified F-H model to interpret the partition data of compounds with organic solvents.

UR - http://www.scopus.com/inward/record.url?scp=84882626050&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84882626050&partnerID=8YFLogxK

U2 - 10.1007/s10953-013-0041-7

DO - 10.1007/s10953-013-0041-7

M3 - Article

VL - 42

SP - 1438

EP - 1451

JO - Journal of Solution Chemistry

JF - Journal of Solution Chemistry

SN - 0095-9782

IS - 7

ER -