Responses of 6FDA-based polyimide thin membranes to CO₂ exposure and physical aging as monitored by gas permeability

Membranes made from glassy polymers have been of great interest in the past decade for CO₂ removal from natural gas streams; however, strongly soluble gases, such as CO₂, can cause “plasticization” of polymer membranes, which greatly reduces the separation efficiency. This work examines the response...

Full description

Saved in:
Bibliographic Details
Published in:Polymer (Guilford) 2011-11, Vol.52 (24), p.5528-5537
Main Authors: Cui, Lili, Qiu, Wulin, Paul, D.R, Koros, W.J
Format: Article
Language:English
Subjects:
Aging (natural)
annealing
Applied sciences
Carbon dioxide
Crosslinking
decarboxylation
Exact sciences and technology
Exchange resins and membranes
Forms of application and semi-finished materials
gases
Membranes
Natural gas
Permeability
Polyimide resins
Polymer industry, paints, wood
polymers
Technology of polymers
Thin films
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Membranes made from glassy polymers have been of great interest in the past decade for CO₂ removal from natural gas streams; however, strongly soluble gases, such as CO₂, can cause “plasticization” of polymer membranes, which greatly reduces the separation efficiency. This work examines the response of several 6FDA-based polyimides thin film membranes with thicknesses around 200 nm to CO₂ exposure and physical aging. DABA units are incorporated to create crosslinkable sites for such materials. Introducing DABA units to the 6FDA-DAM and 6FDA-mPDA polymers seems to result in materials even more prone to CO₂ plasticization. A unique thermal annealing approach is used to crosslink the polyimides via decarboxylation of the DABA units; the resulting crosslinked polymers appear to be much more plasticization resistant at high CO₂ pressures compared to their DABA containing counterparts prior to crosslinking. Prior thermal history plays a significant role in both the physical aging of the thin film membranes and their CO₂ plasticization resistance particularly for chemical structures that tend to lead to high free volume and permeability.
ISSN:0032-3861
1873-2291
DOI:10.1016/j.polymer.2011.10.008