Piperazine derivatives as chain extenders in polyurea elastomer systems and method of making same.

摘要

Polyurea elastomers are produced by reacting an isocyanate with an amine-terminated polyoxyalkylene polyol in the presence of a chain extender according to the invention, the chain extender comprises a minor amount of tetraalkylpiperazine, preferably tetramethyl piperazine, and a major amount of diethyl toluene diamine. The invention also provides a method for synthesizing tetraalkylpiperazines simultaneously with tetraalkylpiperazinones, by reacting a 2-amino-2-alkyl-1-alkanol in the presence of a nickel plus transition metal catalyst.