Catalytic process for the preparation of linear polyethylenepolyamines with tungstophosphoric acid-or molybdophosphoric acid-on-titania catalysts

Granted: Jul 28, 1987 Filed: Sep 18, 1986

This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.