PROCESS FOR MAKING POLYETHER ALCOHOLS HAVING OXYETHYLENE UNITS BY POLYMERIZATION OF ETHYLENE CARBONATE IN THE PRESENCE OF DOUBLE METAL CYANIDE CATALYSTS

摘要

Ethylene carbonate is polymerized by itself or together with another cyclic monomer such as 1,2-propylene oxide in the presence of a double metal cyanide catalyst. Most of the ethylene carbonate adds to the chain to form a terminal carbonate group, which decarboxylates to produce a hydroxyethyl group at the end of the polymer chain. The polymerization of more ethylene carbonate onto the chain end results in the formation of poly(ethyleneoxy) units. Therefore, the process provides a method for making poly(ethyleneoxy) polymers without the need to polymerize ethylene oxide. The process is useful for making polyethers that are useful as water-absorbable polymers, surfactants and as raw materials for polyurethanes. The process is also useful for increasing the primary hydroxyl content of a polyether.