Effects of Chemical Treatments on Ultra-High-Yield Pulping. VI. The Relative Effect of Lignin Oxidation and Sulfonation

ABSTRACT The chemical properties and performance of aspen percarbonate (P) and sulfite (S) chemimechanical pulp (CMP) fibers are very comparable. The PCMP, when compared with SCMP of the same yield, has a slightly higher tear index, same beatability and light scattering coefficient, but a lower tensile index and brightness. The strength properties of these fibers are closely related to the total acidic group content resulting from lignin oxidation (carboxyls) and sulfonation (sulfonate).