The role of both dimeric and monomeric forms of acrylamide monomer in the process of polymerization in emulsions initiated by different type of initiators was discussed and the reasons for the reaction order with respect to monomer greater than unity were elucidated for acrylamide free radical polymerization in emulsions. The emulsion polymerization mechanism of acrylamide is discussed separately for the processes initiated by water-soluble initiator and oil-soluble initiator. The main difference in two cases is the distribution of acrylamide and initiator in aqueous and toluene phases. In the case of using water-soluble initiator, the initiator and acrylamide are in the same phase, whereas the molecules of the initiator and acrylamide are distributed between different phases in the case of using oil-soluble initiator. As a result, the participation of the dimers in the process of acrylamide emulsion polymerization is more efficient for the system where water-soluble initiator is used. For that system, it is suggested that both dimers and monomers of acrylamide participate in the propagation reaction at relatively low concentrations of acrylamide, which explains the value of the reaction order with respect to monomer greater than unity.
The role of alcohols in the polymerization of NCA's by alkaline alkoxides. Dualism of the polymerization mechanism
