Patent ID: 11629225

Abstract:
Processes are described for producing an aromatic diamine-initiated polyether polyol having a measured OH number of 300 to 500 mg KOH/g and a viscosity at 25° C. of 5000 to 50,000 mPas. The processes include a first alkoxylation step in which an alkylene oxide consisting essentially of propylene oxide is reacted with a starter consisting essentially of aromatic diamine at a molar ratio of propylene oxide to aromatic diamine of 1.4:1 to 2.0:1 to form an alkoxylated product; and a second alkoxylation step in which an alkylene oxide consisting essentially of propylene oxide is reacted with the alkoxylated product, in the presence of an added catalyst, until the ratio of moles of propylene oxide added in the process to the moles of aromatic diamine added in the process is 4:1 to 9:1.