Aqueous Dispersion Polymerization of Amphoteric Polyacrylamide

摘要

The terpolymer of acrylamide (AM), dime-thylaminoethyl methacrylate methyl chloride (DMC), andacrylic acid (AA) was synthesized with their molar ratioof 70 : 15 : 15 through dispersion polymerization in aque-ous solution of ammonium sulfate (AS), using poly(dime-thylaminoethyl methacrylate methyl chloride) (PDMC) asstabilizer and 2,2'-azobis(2-amidinopropane) dihydro-chloride (V-50) as initiator. The particle size of the terpol-ymer ranged from 5 to 8 um and the intrinsic viscositywas from 5.5 to 11.6 dL g~(-1).The terpolymer had anti-polyelectrolyte effect under low AS concentration, butpolyelectrolyte effect with the concentration beyond 10%.Polymerization dispersion with low apparent viscosity,uniform particles, good stability, and high molecularweight terpolymer was obtained in single stage. The effects of varying concentrations of salt, stabilizer, andmonomers on particle morphology and intrinsic viscositywere investigated. With increasing concentration of ASand PDMC, the intrinsic viscosity of terpolymerincreased, then decreased afterward. However, itincreased gradually with increase in monomer concentra-tion. The particle size was enlarged with increasing of ASand monomer concentration and decreasing of PDMCconcentration. The optimum condition was the concentra-tions of salt, stabilizer, and monomers 28%, 3.0%, and 8%to 15%, respectively.