Dextrin-Poly(acrylic acid) Copolymer as an Additive for Surface Sizing with Oxidized Starch : Effect on Viscosity and Retrogradation

Drying energy saving by reducing the steam consumption in the after-dryer section becomes more important for many grades of papers including linerboards because surface sizing gets more widely used for these grades. Drying energy demand in the after-dryer can be decreased by increasing the solids content of the sizing agent. This requires a new sizing agent or additive be developed that provide low in viscosity at higher solids content. A dextrin poly(acrylic acid) copolymer at a solids level of 52% was prepared and used as an additive for surface sizing with oxidized starch. The effect of the copolymer on viscosity, cooking property and retrogradation was examined using Brookfield viscometer and Brabender Viscograph. It was shown that use of the copolymer increased the solids content of sizing solutions and provided better cooking and storage properties. Starch graft copolymer could reduce the reassociation of starch molecules and hinder retrogradation after cooling and during the holding period. KCI Citation Count: 1