Epoxidation of hydroxyl-terminated polybutadiene with hydrogen peroxide under phase-transfer catalysis

The phase-transfer catalytic epoxidation of hydroxyl-terminated polybutadiene (HTPB) by hydrogen peroxide was investigated by using quaternary ammonium salts, ammonium tungstate hydrate and phosphoric acid as the phase-transfer catalyst and cocatalysts, respectively. The influences of quaternary ammonium salts, the amount of Aliquat 336 and hydrogen peroxide, the molar ratio of phosphoric acid to ammonium tungstate hydrate (PO43−/WO42−), pH value and organic solvents on the conversion of double bonds in HTPB polymer were studied in detail. The kinetic of epoxidation of HTPB was also discussed and the apparent activated energy for epoxidation of HTPB was estimated to be 21.04 kJ/mol.

The epoxidized HTPB was successfully and efficiently synthesized by epoxidation of HTPB with 34 wt% H2O2 in presence of quaternary ammonium salts as the phase-transfer catalyst, ammonium tungstate hydrate and 85 wt% phosphoric acid as the epoxidation cocatalyst, and an auxiliary organic solvent.Figure optionsDownload as PowerPoint slide