Ethylene Oxide → Undecylenic Acid

Participants

Reaction Conditions

Reaction Steps

In a 4 l multi-necked flask, 1829.9 g (0.7 mol) of an α,ω-dihydroxypoly(ethylene oxide-propylene oxide) copolymer having a hydroxyl number of 41.5 (mg KOH)/g with 50% by mass propylene oxide content and with ethylene oxide end blocks were heated with 249.4 g (1.4 mol) of undecenoic acid (molar mass: 184.3 g/mol, acid number: 304.4 mg KOH/g) to 70° C. with stirring and then 41.6 g of Novozym® 435 (2% by mass based on the total batch) were added. At 4 mbar and with further continual stirring, and also with the introduction of a gentle stream of nitrogen (˜2000 ml/h), the reaction mixture was reacted for 23 hours. During this time the initial acid number of the reaction mixture fell from originally 35.8 mg KOH/g solids to 1.4 mg KOH/g solids. Following filtration and 2-hour heat treatment at 120° C., the α,ω-bis-undecenoato-poly(ethylene oxide-propylene oxide) copolymer was ready for use for the subsequent reactions.

Provenance & Evidence