Method for producing polyether polymers

A method of making a polyether polymer comprising

• reacting a salt of a dihydroxy-substituted aromatic hydrocarbon with a substituted aromatic compound of formula (I)
• Z(A1—X1)2 (I)
• in the presence of a catalyst to form an intermediate polymer, wherein the molar ratio of the salt of a dihydroxy-substituted aromatic hydrocarbon to the substituted aromatic compound is less than 1, Z is an activating radical, A1 is an aromatic radical and X1 is fluoro, chloro, bromo or nitro;
• determining the molecular weight of the intermediate polymer;
• calculating the amount of the salt of a dihydroxy-substituted aromatic hydrocarbon used to form the intermediate polymer based on molecular weight achieved and an historical trend of molecular weight versus amount of salt used;
• determining an additional amount of a salt of a dihydroxy-substituted aromatic hydrocarbon to obtain a final polymer having a predetermined weight from the intermediate polymer wherein the additional amount of equals (amount of salt of dihydroxy-substituted aromatic hydrocarbon needed per amount of final polymer - amount of the salt of a dihydroxy-substituted aromatic hydrocarbon used to form the intermediate polymer per amount of intermediate polymer) X amount of final polymer;
• reacting the intermediate polymer with the additional amount of the salt of a dihydroxy-substituted aromatic hydrocarbon to form the final polymer.