Studies On Synthesis And Application Of Aqueous Dispersion Of Terpolymer Cationic Polyacrylamide

Cationic polyacrylamide with varities of cationic groups could emerge significant special effects, so it had been one of the most popular researchs in the main research areas of functional polymers. Aqueous dispersion as an environmentally friendly polymerization is the most promising way to synthesis polyacrylamide, which is easy to realize and the product is harmless.On the basis of the relevant literature, the preparation rules, stability rules and flocculating performance of the aqueous dispersion of terpolymer cationic polyacrylamide, were systematic investigated in this thesis.This research selected acrylamide(AM) as main raw material, dimethylaminoethyl methacrylate methyl chloride (DMC) and methyl acryloyloxyethyl benzyl dimethyl ammonium chlorideas (MBDAC) as cationic monomers, poly(dimethylaminoethyl methacrylate methyl chloride)(PDMC) as stabilizer and azo-compounds as initiator, the terpolymer cationic polyelectrolyte of P(AM-DMC-MBDAC) was synthesized by aqueous dispersion polymerization in the ammonium sulfate solution.The effects of varying factors, i.e. the molar ratios of DMC and MBDAC/AM, the total concentration of monomers, the concentration and molecular weight of the dispersant, the concentration of ammonium sulfate, the dosage of initiator and the temperature on the polymerization, the product characters (molecular weight, conversion rate and apparent viscosity) and the stability of the system were investigated. To make the aqueous dispersion stable such condition must be got:the mass fraction of initiator between7‰～10‰, the polymerization temperature between 50-65℃, the mass fraction of stabilizer between1.5%～5.0%, the mass fraction of AS between19%-29%. The dispersion copolymers were characterized with Fourier Transform Infra-Red (FTIR), H NMR spectroscopy(’H NMR).The high molecular weight CPAM was used as flocculant to treat waste water, which was simulated by kaolin. The influences of the concentration, the molecular weight, stirring time, stirring speed and the pH of the waste water system. It was found that when the dosage of P(AM-DMC-MBDAC) reach1mg/L, the removal rate could reach96%. The appropriate stirring time, stirring speed was10min and350r/min. When the pH of the system was below7or the the molecular weight was higher than300×104decontamination effect of the flocculant was much more better.