Optimizing the Properties of Waxy Starches for Alkaline Papermaking, 1990 Papermakers Conference Proceedings

Penelope A. Patton--The specific contributions of the level of cationic charge, anionic charge and molecular weight, of the wet end starch, to the properties of alkaline paper have been investigated. The affects of each starch property on paper properties were studied using conventional handsheet methods, and the data evaluated using regression analysis. We have found that high cationic charge is beneficial for sizing (both ASA and AKD) and filler retention. At high levels of phosphation (0.52% bound phosphate) some benefit is seen in filler retention. However, at this level of phosphation, substantial decreases are seen in both ASA and AKD sizing. High starch molecular weights are beneficial for drainage and retention. Lower molecular weights cause substantial improvement in sizing. HST values for AKD-sized papers reach a maximum at starch intrinsic viscosities of about 1.3. With ASA-sized papers no maximum was seen; the lowest molecular weight starch studied (1.0 intrinsic viscosity) gave the highest level of sizing. Paper strength properties were largely insensitive to changes in these starch properties.