Low molecular weight poly(acrylic acid-co-vinyl aminomethylene phosphonic a
cid)s were prepared by consecutively applying the Hofmann degradation and t
he Mannich reaction to polyacrylamide and poly(acrylamide-co-acrylic acid)s
. H-1-NMR, P-31-NMR, and microanalysis were used for structural analyses. T
hese polymers were tested as anti-scalent and they showed better anti-scale
nt effect than commercial poly(acrylic acid)s. The scale inhibition propert
ies of copolymers increased with increasing amount of aminomethylene phosph
onic acid groups. (C) 2000 John Wiley & Sons, Inc.