Acrylic Water Soluble Polymers
The mechanism of the free radical polymerization of acrylic water soluble monomers has been elucidated. Donor-acceptor interactions between initiator and monomer form a weak charge transfer complex which acts as a secondary source of initiation. This accounts for the unusually high rate dependence on monomer concentration observed for nonionic, anionic and cationic monomers. In polymerizations where the initiator and monomer are segregated, as for example in inverse-microsuspension, monomer enhanced decomposition is absent. Three other reactions dominate: unimolecular chain termination with interfacial emulsifier, heterophase diffusion of primary and oligoradicals and long chain branching with unsaturated carbons on the terminal oleate groups.
A new light scattering procedure has been developed based on the theoretical prediction of the second virial coefficient. The method eliminates greater than fifty percent of the variance in estimation of molecular weight, concomitant with a fivefold reduction in measurement time, and can be applied to any linear polymer, including polyelectrolytes.