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Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
Published on: December 16, 2022
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Side-Chain Length and Dispersity in ROMP Polymers with Pore-Generating Side Chains for Gas Separations
Francesco M Benedetti1, You-Chi Mason Wu2, Sharon Lin1
1Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
JACS Au
|August 1, 2022
Summary
This study shows that bottlebrush polymers with longer, uniform side chains enhance carbon dioxide (CO2) separation. Longer side chains improve gas permeability and plasticization resistance in membranes.
Area of Science:
- Polymer Science
- Materials Science
- Chemical Engineering
Background:
- Bottlebrush polymers with flexible backbones and rigid side chains exhibit high CO2 permeability and resistance to plasticization for gas separations.
- Previous studies primarily used polydisperse side chains, limiting understanding of side-chain length effects.
Purpose of the Study:
- To investigate the impact of uniform side-chain length on gas transport properties and plasticization resistance in methoxy (OMe)-functionalized bottlebrush polymers.
- To elucidate the role of side-chain length and dispersity in membrane-based gas separations.
Main Methods:
- Synthesis of OMe-functionalized bottlebrush polymers via ring-opening metathesis polymerization (ROMP) with controlled side-chain lengths (n=2 to 5).
- Characterization of polymer properties including Brunauer-Emmett-Teller (BET) surface area.
- Measurement of gas transport properties (permeability, selectivity) and plasticization resistance.
Main Results:
- Increasing side-chain length led to higher BET surface area and enhanced gas permeability.
- Gas selectivity remained largely unaffected by increased side-chain length.
- Longer side chains improved plasticization resistance due to increased interchain rigidity.
Conclusions:
- Controlling side-chain length in ROMP polymers is a viable strategy for optimizing performance in CO2 gas separations.
- Uniform side chains offer a pathway to tune polymer properties for advanced membrane applications.
- This research provides insights into rational design of polymers for efficient gas separation membranes.
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