The Preparation Of Chitosan Grafted With Maleic Anhydride And Itaconic Acid And The Research Of The Inhibition Performance

This paper was mainly about the preparation of three grafted compound, which contains chitosan, maleic anhydride and itaconic acid. Chitosan is a kind of nature high molecular polymer with -OH,-NH2 groups. Because of the low toxic, readily biodegradable advantages, many researchers pay attention to the application of chitosan in water treatment field. Maleic anhydride is another kind of raw material in water treatment, which is effective and low toxic. Itaconic acid has active chemical property. Chitosan was selected as the subject grafted with maleic anhydride and itaconic acid to prepare a novel effective and green scale inhibitor. The inhibition performance of the grafted compound is studied.Firstly, taking chitosan as the main material, taking ammonium per sulfate as initiator, under the protection of N2, the grafted reaction to get the three grafted compound was carried on. Considering the grafted rate, the best conditions were: concentration of initiator =3.2×10-2 mol/L;reaction temperature =50℃; reaction time =5h; n(MA):n(IA) =1:1.5; m(chitosan):m(maleic+itaconic)=1:3.Secondly, infrared spectrometer,X-Ray diffraction,thermo gravimetric analysis, element analysis, scanning electron microscope methods were used to characterize three grafted compound. The characterization with several difference showed that maleic anhydride and itaconic acid are grafted on chitosan subject.Thirdly, the inhibition performance of the grafted compound was studied by the static anti-scaling method. The conditions were: concentration of scale inhibitor =60mg/L; PH =8; constant temperature =(60士1)℃; constant time =8h; concentration of Ca2+ =500mg/L. The inhibition rate can reach 90% and above. And the inhibition mechanism was studied, the theory of lattice disformation was possible.Finally, the inhibition performance with other scale inhibitors, such as HPMA and AMPS were compared.