Solubilization of zein in N,N-dimethylacrylamide (DMAAm) followed by DMAAm polymerization affords pseudoplastic blends and stable semiinterpenetrating networks (IPNs) of the protein with polyDMAAm. Thermoinduced aggregation of hydrophobic chains of zein in the IPNs is shown to be reversible. Mechanistic concept is forwarded that allows explanation of the blends’ thermo-thinning and shear-thinning behavior as well as temperature-induced changes in the IPN permeability.