Title: METHOD FOR PRODUCING SOFT POLYURETHANE FOAM BASED ON POLYESTER POLYOLS
Number/Link: WO2014/064130
Applicant/Assignee: Bayer
Publication date: 1-05-2014
“Gist”: Flexible foams can be prepared from polyester polyols based on two different diacids and with a limited ester group content.
Why it is interesting: According to this invention flexible foams can be based on polyester polyols only if the polyols are not too polar or too ‘symmetrical’. This is achieved by preparing the polyols from at least two diacids chosen from (preferably) succinic-, adipic-, azeleic- or sebacic acid, together with (e.g.) diethylene grlycol and some trimethylolpropane. Both the acids and the alcohols are preferably bio-based. The polyester polyols have an OH value of about 60 and an ester group content (polarity) of less than 9.8 mol/kg. In comparative examples flexible foams based on polyester polyols containing only one diacid showed collapse.

