Title: POLYURETHANES HAVING REDUCED ALDEHYDE EMISSION
Number/Link:WO2015/082316 (German)
Applicant/Assignee: BASF
Publication date: 11-06-2015
“Gist”: Use of CH-acidic compounds as aldehyde scavengers
Why it is interesting: Reducing VOC emissions, and especially aldehyde emissions, from polyurethane systems remains an important research topic and has been discussed before on this blog (see e.g. here and here). To reduce aldehyde emissions, scavenger molecules are used which are often amines or hydrazine compounds. In this invention however the aldehyde scavenger is a CH-acidic compound of the form R-CH2-R’ in which R and R’ are electron-withdrawing groups. The R-groups can be iso-reactive and the molecule can (preferably) contain more than one acidic CH2 group, like e.g. trimethylolpropane triacetoacetate. Other examples are N,N-dimethylacetoacetamide and dimethyl 1,3-acetonedicarboxylate. The compounds are used in an amount of 0.5 to 1 pphp, are said to have advantages over the prior art like less or no catalytic activity and do not lead to extra emissions.