Patent ID: 7671172

Claim:
A process comprising: (a) providing (1) 1,3-propanediol reactant, (2) ethylene glycol reactant and (3) an acid polycondensation catalyst selected from the group comprising of sulfuric acid, fluorosulfonic acid, p-toluenesulfonic acid, benzenesulfonic acid, trifluoromethanesulfonic acid, 1,1,2,2 tetrafluoroethanesulfonic acid, and 1,1,1,2,3,3 hexafluoropropanesulfonic acid; (b) polycondensing the 1,3-propanediol and ethylene glycol reactants in the presence of the acid polycondensation catalyst to form poly(trimethylene-ethylene ether)glycol; and (c) hydrolyzing the poly(trimethylene-ethylene ether)glycol from step (b) to remove sulfate ester groups.