Inverse Emulsion Polymerization Of Acrylamide/Methylacryloylxyethyl Trimethylammonium Chloride

Inverse emulsion copolymerization of acrylamide(AM)and methylacryloylxyethyl trimethylammonium chloride(DMC)using 2,2'-azobis[2-(2-imidazolin-2-yl)propane]-dihydrochloride as initiators,sorbitan monooleate(Span 80)and polyethylene glycol sorbitan monooleate(Tween 80)as composite surfactants,amphiphilic cationic polymer,poly(acryloyloxyethyl dimethylbenzyl ammonium chloride)(PAODBAC),as an additive for the stabilization of water-in-oil inverse emulsions has been studied.The amphiphilic cationic polymer introduced in the system has the same applications as the cationic water-soluble polymer,and does not reduce the utility of the inverse emulsion or its products in industrial fields such as wastewater treatment,papermaking and oil industry.In this work,the effects of various factors on the stability of the inverse emulsion were studied.The effect of PAODBAC added to water phase on the stability of inverse emulsion was investigated.The interaction behavior of PAODBAC and surfactants in the oil and water phases was studied,and mechanism by which the amphiphilic cationic polymer stabilizes inverse emulsion systems was proposed.Then,the nucleation mechanism of inverse emulsion polymerization initiated by water soluble initiator was discussed,and monomer reactivity ratios of AM and DMC were determined.At last,the effects of factors in the system on polymerization kinetics were researched.The effects of emulsifier content,HLB,oil-water mass ratio and monomer ratio on the stability of inverse emulsion were studied by high-speed centrifugation method.The stability of inverse emulsion increased with the increasing of AM content.Adding amphiphilic cationic polymer PAODBAC into the system can improve the stability of inverse emulsion.Determination of surfactant content in water phase by bromination method and the determination of transmittance of oil phase and water phase by ultraviolet spectrophotometer showed that the PAODBAC chains could interact with the surfactant molecules.When PAODBAC is added into the oil and water phase system containing surfactant,the oil-water interface could be completely covered by the surfactants at a lower concentration of PAODBAC.When the concentration of PAODBAC was 0.067%(w/w),the interactions between its chains and the surfactant molecules were optimized,the stability of the inverse emulsion was maximized.At PAODBAC contents of 0-0.067%(w/w),the stability of the inverse emulsions increased with increasing of polymer content due to increased interfacial layer strength between the particles.However,when the concentration of PAODBAC exceeded 0.067%(w/w),the stability of the inverse emulsions decreased for the aggregation of the polymer chains.The presence of PAODBAC in the inverse emulsion system increased the particles size,but aided the establishment of a narrow mean particle size distribution.The linear viscoelastic region of the inverse emulsion corresponded to strains between 0.01 and 0.5%.At polymer concentrations below 0.5%,the G' values of inverse emulsions prepared with PAODBAC were higher than those of inverse emulsions without it.The most stable inverse emulsion exhibited the best elastic behavior.The effect of monomer,initiator,emulsifier and polymerization temperature on the inverse emulsion polymerization rate was determined by dilatometer method.The rate equation of AM and DMC inverse emulsion polymerization could be represented as Rp =k[M]2.12[I]0.55[E]0.65,and the apparent activation energy of AM and DMC inverse emulsion polymerization was 80.65 kJ/mol.Relationship of reaction rate change in AM and DMC inverse emulsion polymerization with time indicated that the nucleation mechanism tended to droplet nucleation.Monomer reactivity ratios of AM and DMC were determined as rAM=0.23,rDMC=1.93 by Fineman-Ross methods.The results showed that random copolymerization of AM and DMC occurred on the polymer chains.The intrinsic viscosity of copolymer could be increased by enhancing the content of monomer,decreasing the dose of initiator,increasing the amount of emulsifier and reducing the reaction temperature.