Polymerization process for preparation of acrylamide homopolymers with

Abstract

There is disclosed a process for the aqueous polymerization of acrylamide to produce polymers of high molecular weight utilizing mixtures of water and monomer, at least one of which can be contaminated with small amounts of polymerization inhibiting components. In the process of the invention, a minimum amount of a redox pair catalyst is utilized in order to obtain the desired high molecular weight polymer. The minimum amount of catalyst is automatically provided to the polymerization mixture by adding a first member of a redox pair to the polymerization mixture and intimately combining a second member of the redox pair catalyst with an organic polymer capable of forming a colloidal dispersion in an aqueous medium and adding this intimate mixture to the mixture of water, acrylamide monomer, and a first member of the redox pair catalyst. The process disclosed provides for the slow release of one member of the redox pair catalyst from said intimate mixture into an aqueous solution or emulsion polymerization medium. As polymerization proceeds, an additional amount of catalyst is made available by the slow recess of one member of the redox pair into the aqueous polymerization medium. The polymerization process can be initiated and maintained at ambient temperatures and pressures. Thus polymerization is effected without providing additional heat or pressure to the reaction mass. Molecular weights of about 1 million to 10 million can be obtained where monomer concentrations are held between about 10 to about 50 percent by weight of the polymerization mixture.