Process for working-up polyethersiloxanes
OwnerGeorg Burkhart, Wilfried Knott +1inventors
InventorsGeorg Burkhart, Wilfried Knott, Volker Mohring
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Abstract
The invention relates to a process for working up polysiloxane/polyoxyalkylene block copolymers, wherein said copolymers are subjected to a treatment with superheated steam.
Claims13
A process for removing impurities from a polysiloxane/polyoxyalkylene block copolymer which comprises treating a polysiloxane/polyoxyalkylene block copolymer containing said impurities with superheated steam.
A method for removing odors from a polysiloxane/polyoxyalkylene block copolymer which comprises treating a polysiloxane/polyoxyalkylene block copolymer with superheated steam.
A process for preparing a flexible polyurethane foam which comprises reacting a polyol and an isocyanate in the presence of a foam stabilizer, wherein the foam stabilizer comprises a polysiloxane/polyoxyalkylene block copolymer, whereby the polysiloxane/polyoxyalkylene block copolymer first has been purified by reacting said polysiloxane/polyoxyalkylene block copolymer with superheated steam.
A polysiloxane/polyoxyalkylene block copolymer wherein said polysiloxane/polyoxyalkylene block copolymer has, as impurities, less than 1 ppm of propionaldehyde and less than 0.1% of D4, D5 or D6 cyclic siloxanes.
Dependencies are inferred from the claim text.