The catalytic influence of bivalent metal ions on tannin formaldehyde reaction has been investigated, wing three different methods (1): Hydroxylamine hydrochloride (2), Viscometry and (3) IR Spectroscopy. The results obtained from the first and third methods are comparable, while a slight deviation in the order of effectivity was observed in the case of second method due to die stability of the intermediate complexes. It was also observed that transition metals catalysed the reaction more effectively than alkaline earth metals.


SABINA NAZLI ,MANSOOR AHMAD ,