| abstract |
The use of an aldehyde mixture containing 70 to 95 wt % of aldehydes of formula (I) and 5 to 30 wt % of alkylbenzene compounds not corresponding to formula (I) as a blocking agent for amines results in odorless, especially economically blocked amines, which at room temperature are typically liquid and have a surprisingly low viscosity. Such blocked amines are particularly suitable as latent hardeners in isocyanate-group-containing compositions. Single-component moisture-curing polyurethane compositions formulated therewith are surprisingly stable in storage, can be used for low-emission applications without odor problems and do not trigger any problems with plasticizer migration. Surprisingly, said compositions even have advantages over corresponding compositions having latent hardeners based on purified aldehydes of formula (I), in particular with respect to viscosity, storage stability and especially strength. |