Patent ID: 8372946

Claim:
A continuous process for manufacturing copolyether glycol having a high molar incorporation of alkylene oxide of at least about 50 mol %, a mean molecular weight of from about 650 dalton to about 4000 dalton and a viscosity of from about 80 cP to about 4000 cP comprising the steps of: a′) polymerizing in a continually stirred tank reactor from about 15 to about 90 parts feedstock comprising from about 10 to about 90 wt % tetrahydrofuran and from about 10 to about 90 wt % of at least one alkylene oxide, in the presence of from about 0.1 to about 5 wt % of at least one compound containing reactive hydrogen atoms, from 10 to about 40 wt % of inert diluent or solvent, and an acid polymeric catalyst containing sulfonic acid groups at a temperature of from about 30° C. to about 80° C. to produce a polymerization product mixture comprising OCE, copolyether glycol having a high molar incorporation of alkylene oxide of at least about 50 mol %, a mean molecular weight of from about 650 dalton to about 4000 dalton and a viscosity of from about 80 cP to about 4000 cP, at least one dimer of the alkylene oxide, linear short chain copolyether glycol and tetrahydrofuran; b′) separating a majority of the tetrahydrofuran and the dimer of the alkylene oxide from the polymerization product mixture of step a′) to produce a crude product mixture comprising OCE, copolyether glycol having a high molar incorporation of alkylene oxide of at least about 50 mol %, a mean molecular weight of from about 650 dalton to about 4000 dalton and a viscosity of from about 80 cP to about 4000 cP, and linear short chain copolyether glycol; c′) separating at least a portion of the OCE and linear short chain copolyether glycol from the crude product mixture of step b′) to produce an OCE stream comprising OCE and linear short chain copolyether glycol, and a product stream comprising copolyether glycol having a high molar incorporation of alkylene oxide of at least about 50 mol %, a mean molecular weight of from about 650 dalton to about 4000 dalton and a viscosity of from about 80 cP to about 4000 cP; d′) optionally recycling at least a portion of the OCE stream of step c′) to the polymerization step a′); and further comprising filtering the polymerization product mixture of step a′) prior to step b′), and filtering the crude product mixture of step b′) prior to step c′).