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Claisen thermally rearranged (CTR) polymers
Alberto Tena1, Sofia Rangou1, Sergey Shishatskiy1
1Institute of Polymer Research, Helmholtz-Zentrum Geesthacht, Max-Planck-Str.1, 21502 Geesthacht, Germany.
Science Advances
|August 3, 2016
Summary
New thermally rearranged (TR) polymers achieve high conversion at lower temperatures using [3,3]-sigmatropic rearrangement. These advanced materials offer enhanced permeability for efficient membrane separations.
Area of Science:
- Polymer Science
- Materials Science
- Chemical Engineering
Background:
- Thermally rearranged (TR) polymers are promising membrane materials due to excellent transport properties and stability.
- Existing TR polymers suffer from high processing temperatures and low conversion rates.
- Developing efficient TR polymers is crucial for advanced separation applications.
Purpose of the Study:
- To reduce the high temperatures required for polymer rearrangement.
- To improve the degree of conversion in solid glassy polymers.
- To develop next-generation TR polymers for efficient membrane applications.
Main Methods:
- Utilized a [3,3]-sigmatropic rearrangement mechanism.
- Applied the method to functionalized polyimide polymers.
- Achieved high conversion to polybenzoxazole.
Main Results:
- Reduced rearrangement temperature by 200°C compared to conventional methods.
- Achieved over 97% conversion of polyimide to polybenzoxazole.
- Resulting polymers exhibited five times higher permeability and double the conversion rate compared to reference polymers.
Conclusions:
- The [3,3]-sigmatropic rearrangement significantly enhances TR polymer synthesis efficiency.
- Second-generation TR polymers demonstrate superior properties for membrane applications.
- These findings enable the creation of efficient thin-film composite membranes for gas and liquid separations.
Keywords:
Claisen rearrangementLow-temperature thermally rearranged polymergas separationmembranenatural gas purificationpolybenzoxazole (PBO)polymer modificationMore Related Videos
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