Manufacture of paper using copolymers of 2-acrylamido-2-methylpropane sulfonic acid for increasing rate of dewatering of high mechanical/thermomechanical pulp furnishes.

摘要

A process for increasing rate of dewatering in the manufacture of paper from an aqueous furnish which comprises at least 40% by weight of mechanical wood pulp, thermomechanical wood pulp, or mixtures thereof, by addition thereto of an aluminum salt, e.g., alum, and a water-soluble copolymer containing from about 2 to about 30 mole percent repeating units derived from 2-acrylamido-2-methylpropane sulfonic acid, from 0 to about 25 mole percent repeating unit derived from acrylic acid, and from about 45 to about 98 mole percent repeating units derived from acrylamide, while maintaining pH of the furnish in the range of from about 3.5 to about 6.5.