(193ah) Highly Polar Polymers Based on Poly(1,3-dioxolane) for Membrane CO2/N2 Separation

Authors: 
Liu, J., University at Buffalo, The State University of New York
Park, H. B., Hanyang University
Lin, H., University at Buffalo, The State University of New York

Highly
Polar Polymers based on Poly(1,3-dioxolane) for Membrane CO2/N2
Separation

Junyi
Liu1, Ho Bum Park2, Haiqing Lin1

 

1Department of
Chemical and Biological Engineering, University at Buffalo, The State
University of New York, Buffalo, NY, USA

2WCU Department of
Energy Engineering, Hanyang University, Seoul, South Korea

Email
address: junyiliu@buffalo.edu, badtzhb@hanyang.ac.kr, haiqingl@buffalo.edu

Prepared for 08A07
Diffusion in Polymers 

Membrane materials
with high CO2 permeability and high CO2/N2
selectivity are in pursuit for CO2 capture from flue gas derived
from fossil fuel-power plants. The leading
materials usually contain
poly(ethylene oxide) (PEO) because the ether oxygens in PEO interact favorably
with CO2,
resulting in
high CO2 sorption and permeability, and thus high CO2/N2
selectivity.
In this study,
we demonstrate that polymers with higher ether oxygen content than PEO exhibit
better CO2/N2 separation performance. Specifically, a
family of polymers containing poly(1,3-dioxlane) (with an O:C ratio of 1:1.5,
compared with 1:2 in PEO) were synthesized by photopolymerization of two
macromonomers,
poly(1,3-dioxolane)
acrylate (PDXLA) and poly(1,3-dioxolane) ethyl ether acrylate (PDXLEA). Both
macromonomers at different chain lengths were prepared via cationic ring
opening polymerization of 1,3-dioxolane. The macromomoners and polymers are
systematically characterized for chemical structures and physical properties using
NMR, DSC,
FTIR,
XRD, etc. Pure-gas solubility and pure‑ and mixed-gas permeability were
determined as a function of pressures and temperatures. These highly polar
polymers
exhibit CO2/N2
separation properties above the upper bound in the Robeson’s plot, and better
than PEO based materials. For example, a copolymer prepared from PDXLA and PDXLEA
at a weight ratio of 1:3 (i.e., PDXLEA75) exhibits a mixed-gas CO2
permeability of 1300 Barrers and CO2/N2 selectivity of 62
under humidified environment at 70 oC. The structure/property
relationship in this series of copolymers will be elucidated, and their
potential for membrane materials for industrial CO2 capture from
flue gas will be discussed.