Rapid Determination of Amine and Amide Wet Strength Resins in Aqueous Solution and in Dry Paper/Board, 1990 Papermakers Conference Proceedings

Robert J. Mills--The motivation for the work that will be presented here, came from experiences in chemical qualifying trials using wet strength resins. Following start-up on a new chemical, the technical representative is frequently called on to evaluate the performance while the machine is making 1000 tons per day, which means that by the time the first turn-up occurs, over 6,000 pounds of paper has been made. By the time wet and dry tensiles, mullens and size tests are in, the second turn-up is imminent, so realistically, more than 12,000 pounds of paper is produced before finding out if everything is working well. It seemed obvious that if the chemistry and engineering homework had been done, there was no reason to doubt a successful trial would result assuming the product was applied, dispersed in the approach system and retained above the wire properly. Of course there is little to be done once the resin is in the wet mat and entering the press section. However, when resin is added at the fan pump of a high fines wet end system, conditions exist for recirculating resin on fines which can cause the following performance and process problems: - Reduced efficiency of strength developed - Enhanced foaming tendencies of white water - Upsetting wet end chemistries The objective of this study was to develop a test for wet strength resin in white water with the premise that if a great volume of resin was detectable in the recirculating water system, there would be a corresponding lack of efficiency in the finished paper.