The Aqueous Two-phase Copolymerization Of Acrylamide And Sodium Acrylate

Aqueous two-phase polymerization is that the water-soluble monomers,initiator andanother water-soluble polymer are dissolved to form a homogeneous aqueoussolution,then polymerize to form a heterogeneous polymeric disperse aqueoussolution.The two polymers enriched in the disperse and continuous phaserespectively.It overcame the problems of mixing and heat transfer of polymerizationsystem.The aqueous two-phase polymerization was performed in water without anyorganic solvent.It also overcame the pollution and recycle problems of organic solventfor inverse phase suspension polymerization,water-in-oil inverse phase emulsionpolymerization and precipitation polymerization.It's a new polymerization method forpreparing the water soluble copolymer .It was reported rarely that two water-solublepolymers were dissolved in another water-soluble polymer to copolymerize to formaqueous two-phase polymerization.In this paper,arylamide and acroleic acid sodiumwere selected to form aqueous two-phase polymers,then copolymerization was studied.Polyethylene glyol aqueous solution was selected as the dispersed medium of theaqueous two-phase polymerization for acryamide and acroleic acid sodium systembased on the hydrophobic interaction among water-soluble polymers.The viscositynumber of polymer aqueous solution and the stability of the polymerization system.theeffects of different molecular-weight PEG on emulsion state and stability werestudied,and finally the PEG20000 aqueous solution was the dispersion.The effect of initiator concentration,EDTA concentration,initial monomerconcentration,sodium formate and carbamide concentration,temperature ofpolymerization,pH of the system, monomers,emulsifier and intrinsic viscosity numberof HPAM on stability of HPAM-PEG aqueous emulsion system and monomeruntransformed ratio was studied.At last,by orthogonal,the optimum techonologicalparameters were fixed,and also the best HLB value.The effect of several technological parameters on polymerization velocity werestudied by dilatometer and the kinetics equation and activation energy.In this case,theeffect of the polarity of medium on reactivity ratio was a little by using partialhydrolysis degree to calculate anion degree to measure the reactivity ratio and usingF-R and other methods to measure it.In the last chapter,the phase diagrams of HPAM-PEG-water aqueous system wereobtained by turbidity titration,and the effects of temperature and the molecular weightof PEG were studied.With the increase of the molecular weight of PEG,the criticalphase splitting concentration decreased;with the increase of the temperature,the criticalphase splitting concentration decreased and then increased,it was lowest as whentemperature was 60℃.PEG and the phase enriched in HPAM were different inhydrophobic quality,so AM was dispersed into two phase,as the concenteation ofHPAM increased,the distribution number of AM increased;as the concentration of PEGincreased,the distribution number of AM decreased;as the temperature increased thedistribution number increased.According to the works and experiences,the stabilitymechanism of HPAM-PEG-water aqueous emulsion was discussed primarily.Thefactor were: the high viscosity in the droplet,the viscosity of continuous phase and thestatic electrification fragment.