Alkylene oxide-lactone copolymers

摘要

A block copolymer is disclosed, which comprises a first block comprising polymerised units of an alkylene oxide and a second block comprising polymerised units of an alkylene oxide and a lactone, said copolymer being obtainable by polymerising an alkylene oxide in the presence of an organic initiator to form said first block and reacting the first block with a mixture of an alkylene oxide and a lactone. Such copolymers are found to have improved foam inhibition characteristics whilst maintaining their biodegradable properties.