Oxygen sequestering agent

The major mode of polyacrylamide decomposition at elevated temperature (in the absence of oxygen) is hydrolysis (319,320). Thus, the concentration of divalent metal ions has an effect on viscosity retention at high temperature. Chelating and sequestering agents have been used to reduce the adverse effect of... 

Increase in the chemical OCD demand in oxygen (polymers and biodegradable organic sequestering agents)... 

Divalent and trivalent transition metal cations (Fe, Cu, Al, Zn, Ni, Cr, etc.) also have several harmful effects, such as flocculation or catalytic destabilization of the bleaching systems that furnish active oxygen, and must, therefore, be eliminated as well. To this end, organic sequestering agents that are more specific to the metallic cations to be removed are used. This subject is, however, on the fringes of the agreed definition of a builder. 

Studied for their antibacterial activity and in this case a metal-sequestering (iron) mechanism is indicated, analogous to naturally-occurring antibiotics. Other chelating agents such as 8-hydroxyquinoline may chelate iron and activate oxygen as a mode of action. 

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