Water as monomer: Synthesis of an aliphatic polyethersulfone from divinyl sulfone and water

Using water as monomer in polymerization reactions presents a unique and exquisite strategy towards more sustainable chemistry. Herein, the feasibility thereof is demonstrated by the introduction of the oxa-Michael polyaddition of water and divinyl sulfone. Upon nucleophilic or base catalysis, the corresponding aliphatic polyethersulfone is obtained in an interfacial polymerization at room temperature in high yield (> 97%) within an hour. The polyethersulfone is characterized by relatively high molar mass averages and a dispersity around 2.5. The polymer was tested as a solid polymer electrolyte with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) as salt. Free standing amorphous membranes were prepared by a melt process in a solvent free manner. The polymer electrolyte containing 15 wt.% LiTFSI featured an oxidation stability of up to 5.5 V vs. Li/Li+ at 45 °C and a conductivity of 1.45 × 10-8 S/cm at room temperature.