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No Polymerization with Metallocenes in Water?-A Prejudice is Refuted
Bart Manders1, Luigi Sciandrone1, Gerhard Hauck1
1BASF AG Polymerforschung 67056 Ludwigshafen (Germany) Fax: (+49) 621-60-56574.
Angewandte Chemie (International Ed. in English)
|May 2, 2018
Summary
Water-sensitive metallocene catalysts are now usable in water-based polymerization. Encapsulation within monomer droplets protects the catalyst, enabling the synthesis of syndiotactic polystyrene in aqueous emulsion polymerization.
Area of Science:
- Polymer Chemistry
- Catalysis
- Materials Science
Background:
- Metallocene catalysts typically require strict anhydrous and anaerobic conditions.
- Aqueous polymerization methods offer environmental and economic advantages but are incompatible with water-sensitive catalysts.
Purpose of the Study:
- To demonstrate the successful application of water-sensitive metallocene catalysts in aqueous emulsion polymerization.
- To develop a method for protecting metallocene catalysts from water during polymerization.
Main Methods:
- Utilized a titanium-based metallocene catalyst, [TiCp*(OMe)3] (Cp*=pentamethylcyclopentadienyl).
- Employed aqueous emulsion polymerization of styrene.
- Investigated catalyst encapsulation within monomer droplets for protection.
Main Results:
- Achieved successful polymerization of styrene in an aqueous emulsion system using a water-sensitive metallocene catalyst.
- Demonstrated that encapsulating the catalyst within monomer droplets effectively shields it from water.
- Produced syndiotactic polystyrene.
Conclusions:
- Water-sensitive metallocene catalysts can be effectively utilized in aqueous polymerization systems.
- Catalyst encapsulation is a viable strategy to enable their use in water.
- This approach opens new possibilities for sustainable polymer synthesis.
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