Poly(oxyalkylene) synthesis in Brønsted acid ionic liquids
Shaodong Zhang1, Aurélie Féret, Hervé Lefebvre
1UPMC Univ. Paris 06, UMR 7610, Laboratoire de Chimie des Polymères, Courrier 184, 94200 Ivry sur Seine, France.
Chemical Communications (Cambridge, England)
|September 13, 2011
Summary
Brønsted Acid Ionic Liquids (BAILs) facilitate polyetherification of diols into high molar mass poly(oxyalkylene)s at 130 °C. Shorter diols like 1,4-butanediol and 1,6-hexanediol predominantly formed cyclic ethers instead.
Area of Science:
- Polymer Chemistry
- Green Chemistry
- Materials Science
Background:
- Polyether synthesis is crucial for materials like polyurethanes and surfactants.
- Traditional methods often require harsh conditions or toxic catalysts.
- Ionic liquids offer tunable properties as reaction media.
Purpose of the Study:
- To investigate the efficacy of Brønsted Acid Ionic Liquids (BAILs) in catalyzing polyetherification.
- To explore the influence of diol chain length on polymer formation.
- To achieve high molar mass poly(oxyalkylene)s under mild conditions.
Main Methods:
- Polyetherification reactions using diols with 4-12 methylene units.
- Utilizing various Brønsted Acid Ionic Liquids (BAILs) as catalysts and solvents.
- Characterization of resulting polymers and byproducts using standard techniques.
Main Results:
- High molar mass poly(oxyalkylene)s were successfully synthesized from longer-chain diols.
- The reactions proceeded efficiently at a relatively low temperature of 130 °C.
- 1,4-butanediol and 1,6-hexanediol primarily yielded cyclic ethers, not linear polymers.
Conclusions:
- BAILs are effective catalysts for synthesizing poly(oxyalkylene)s from suitable diols.
- Diol structure significantly impacts the reaction outcome, favoring cyclization for shorter diols.
- This study demonstrates a greener approach to polyether synthesis.
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