KINETICS OF ACRYLAMIDE POLYMERIZATION IN POLYETHYLENE GLYCOL AQUEOUS SOLUTIONS

The advantages of acrylamide (AM) polymerization in polyethylene glycol (PEG) aqueous solutions are the lower viscosity and higher monomer concentration of the polymerization system.It may be used to prepare water soluble polymers with high molecular weight which can be directly diluted for use.It overcomes the problems of mixing and heat transfer of polymerization systems,low polymerization rate,and qualities of products in the aqueous homogenous polymerization.On the other hand,AM polymerization in PEG aqueous solutions is performed in water without using any organic solvents.It also overcomes the pollution and recycle problems of organic solvents for inverse phase suspension polymerization,water-in-oil inverse phase emulsion polymerization and precipitation polymerization.It is a new polymerization method for preparing water soluble (co)polymers.In this paper kinetics of AM polymerization in PEG aqueous solutions were studied by the improved bromating method.The effects of initiator,monomer and PEG concentrations,emulsifiers with various HLB values,and polymerization temperature on kinetics of AM polymerization in PEG aqueous solutions initiated by single and redox initiators were investigated.It is found that the monomolecular termination is more than the bimolecular one for AM polymerization in PEG aqueous solutions.The apparent activation energy of polymerization initiated by ammonium persulfate-triethanal amine (APS-TEA) redox initiator (E a=42.3 kJ/mol) is smaller than that by single initiator APS (E a=96.1 kJ/mol).