Patents
The invention discloses a process for the preparation of an aromatic tetraamine, namely, {5,5’,6,6’-tetraamino-3,3,3’,3’-tetramethyl-1,1’-spirobi[indane]}. Further, the invention discloses a method for the preparation of polybenzimidazole polymers using the aforesaid aromatic tetraamine which exhibits intrinsic porosity.