Modeling sorption of hydrocarbons in polyethylene with the SAFT-γ Mie approach combined with a statistical-mechanical model to describe semicrystalline polymers
OA Location
Author(s)
Valsecchi, Michele
Galindo, Amparo
Jackson, George
Type
Journal Article
Abstract
A recently developed statistical-mechanical model is applied systematically to estimate the fraction of tie-molecules (polymer chains linking different crystals directly or via entanglements) in semicrystalline polyethylene (PE) samples. The amorphous domains of the polymer are divided into constrained interlamellar domains and “free” outer-lamellar domains. A set of model parameters is assigned to each sample by correlating previous experimental measurements and minimizing the difference between the predicted solubility of pure hydrocarbons in the sample and the experimental values. We show that the sorption isotherms of multiple pure fluids in each sample can be described by a single parameter set, proving that the polymer–solute interactions (described accurately by the SAFT-γ Mie EoS) are decoupled from the sample-specific properties of the polymer. We find that ∼30% of the crystalline stems in the lamellae of PE are connected to tie-molecules, within the bounds suggested by previous theoretical and computational work. The transferability of the sample-specific parameters is assessed by predicting cosolubility effects and solubility at different temperatures, leading to good agreement with experimental data.
Date Issued
2023-12-26
Date Acceptance
2023-09-26
Citation
Macromolecules, 2023, 56 (24), pp.9952-9968
ISSN
0024-9297
Publisher
American Chemical Society
Start Page
9952
End Page
9968
Journal / Book Title
Macromolecules
Volume
56
Issue
24
Copyright Statement
Copyright © 2023 The Authors. Published by American Chemical Society. This publication is licensed under CC-BY 4.0.
License URL
Identifier
https://www.ncbi.nlm.nih.gov/pubmed/38161323
Subjects
1-HEXENE SORPTION
AMORPHOUS PHASES
BULK POLYMERS
CRYSTALLINE POLYMERS
EQUATION-OF-STATE
LINEAR POLYETHYLENE
ORGANIC VAPORS
PERTURBED-CHAIN SAFT
PHASE REACTOR CONDITIONS
Physical Sciences
Polymer Science
Science & Technology
SOLUBILITY
Publication Status
Published
Coverage Spatial
United States
Date Publish Online
2023-12-04