Abstract
Wet strength is a critical property of paper, ensuring structural integrity under moist conditions. A modified cationic polyacrylamide was synthesized to enhance fiber bonding. Laboratory paper sheets treated with modified product with dosages of 2.10–2.52 kg/t showed optimal dry and wet tensile strength. However, pH variations in recycled pulp, especially alkaline conditions caused by calcium carbonate fillers, can reduce additive effectiveness by hydrolyzing aldehyde groups. The study found product performs best at pH 5.5–6.5, without altering the pulp’s initial pH. It shows potential for temporary moisture resistance, with further improvements needed for high-pH environments.