process for the production of polytetramethylaetherglykolen with narrow molecular weight distribution.

摘要

In the preparation of poly(tetramethylene ether) glycol by the polymerization of tetrahydrofuran (THF) using a cationic initiator, molecular weight distribution (MWD) can be held within narrow limits by bringing the THF and the initiator together in a mol ratio such that the degree of polymerization will be at about a minimum and at a temperature which will promote about a maximum number of tertiary oxonium ions, then quickly cooling the reaction mass to -25 DEG C. to +25 DEG C., and then adding enough THF to complete the polymerization. When the desired molecular weight and MWD have been reached, the polymerization is quenched and the polymer isolated.