A solution-processable and ultra-permeable conjugated microporous thermoset for selective hydrogen separation.

Area of Science:

• Polymer Chemistry
• Materials Science
• Separation Technology

Background:

• Cross-linked organic networks offer extreme rigidity but lack processability, limiting their use in applications like molecular sieving.
• Developing polymers that combine plastic-like processability with the structural integrity of cross-linked networks is a significant challenge.

Purpose of the Study:

• To synthesize a novel, solution-processable conjugated microporous thermoset.
• To evaluate its potential as a molecular sieving membrane for gas separations, particularly hydrogen.

Main Methods:

• A simple heating process was used to prepare the conjugated microporous thermoset.
• The material's permanent pore size was characterized (~0.4 nm).
• The material was fabricated into a two-dimensional membrane for gas separation testing.

Main Results:

• The synthesized thermoset is solution-processable and exhibits permanent micropores of ~0.4 nm.
• As a molecular sieving membrane, it demonstrated ultrahigh permeability for hydrogen.
• Excellent selectivity was observed for H2 over various other gases (CO2, O2, N2, CH4, C3H6, C3H8).

Conclusions:

• The developed polymer combines processability, rigidity, and permanent porosity, overcoming limitations of traditional cross-linked networks.
• The solution-processable conjugated microporous thermoset shows significant promise for efficient, large-scale hydrogen separation membranes.
• This material is relevant for commercial and environmental applications requiring advanced gas separation technologies.