A novel water soluble fluorescent monomer

4-(N′-methyl-1-piperazinylallyl)-N-butyl-naphthalimide allyl chloride quaternary ammonium salt (FC) was synthesized from 4-bromo-1

8-maphthalic anhydride and N-methylpiperazidine.Its structure was characterized by IR

1H NMR and elemental analysis.The 2-acrylamido-2-methyl-propanesulfonic acid /acrylic acid copolymer containing fluorescent group (FC-POCA) was prepared by copolymerization of FC

acrylic acid (AA)

2-acrylamido-2-methyl-propanesulfonic acid(AMPS) and NaPO3.The fluorescence and scale inhibition performance of FC-POCA was investigated.The relationship of fluorescence intensity and concentration of FC-POCA was linear

and the correlation coefficient (R) was 0.9578，and the limit of detection was 0.65 mg·L-1.By the static method

the scale inhibition ratio of CaCO3 was 77.2% when the copolymer concentration was 20 mg·L-1，scale inhibition ratio of CaSO4 was 100% when the copolymer concentration was 25 mg·L-1.The results by SEM showed that the copolymer had high performance of scale inhibition on both dispersion and lattice distortion of CaCO3.