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Depolymerizable Olefinic Polymers Based on Fused-Ring Cyclooctene Monomers
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Ultra-High-Molecular-Weight Polymers Produced by the Immortal Phosphine-Based Catalyst System
Yun Bai1, Jianghua He1, Yuetao Zhang1
1State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University, Changchun, Jilin, 130012, China.
Angewandte Chemie (International Ed. in English)
|November 1, 2018
Summary
A novel frustrated Lewis pair catalyst system enables living polymerization of methyl methacrylate to produce ultrahigh molecular weight polymers with controlled properties at room temperature.
Area of Science:
- Polymer Chemistry
- Organometallic Chemistry
- Catalysis
Background:
- Frustrated Lewis pairs (FLPs) are emerging catalysts for polymerization reactions.
- Achieving ultrahigh molecular weight polymers with narrow molecular weight distribution remains a challenge.
Purpose of the Study:
- To develop a novel FLP catalyst for the living polymerization of methyl methacrylate (MMA).
- To achieve ultrahigh molecular weight poly(methyl methacrylate) (PMMA) with controlled molecular weight distribution.
Main Methods:
- Combination of a strong organophosphorus superbase (IAP3) with a sterically encumbered Lewis acid ((BHT)Al i Bu 2).
- Utilizing the FLP system for the catalytic living polymerization of MMA at room temperature.
Main Results:
- Achieved ultrahigh molecular weight PMMA (M n up to 1927 kg mol -1) with narrow molecular weight distribution.
- Demonstrated exceptional catalyst longevity and reinitiation capability after 24 hours at room temperature.
Conclusions:
- The developed FLP catalyst system provides a powerful new method for synthesizing UHMW-PMMA.
- The catalyst's stability and reinitiation properties offer significant advantages for controlled polymerization processes.
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