Abstract
The development of high-performance materials for carbon dioxide separation and capture will significantly contribute to a solution for climate change. Herein, (bicycloheptenyl)ethylterminated
polydimethylsiloxane (PDMSPNB) membranes with varied cross-link densities were synthesized via ring-opening metathesis polymerization. The developed polymer membranes show higher permeability and better selectivity than those of conventional cross-linked PDMS membrane. The achieved performance (CO2 permeabilityÂ…6800 Barrer; CO2/N2 selectivity Â…14) is very promising for practical applications. The key to achieving this high performance is the use of an in situ cross-linking method for difunctional PDMS macromonomers, which provides lightly cross-linked membranes. By combining positron annihilation lifetime spectroscopy, broadband dielectric
spectroscopy, and gas solubility measurements, key parameters necessary for achieving excellent performance have been elucidated.