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Celebrating 100 Issues of Paper360°, Paper360º September/October 2020

Celebrating 100 Issues of Paper360°, Paper360º September/October 2020

Kraft pulp viscosity as a predictor of paper strength: Its uses and abuses, TAPPI Journal October 2023

ABSTRACT: For bleached kraft pulps, two factors govern paper strength: the individual fiber strength, and the bond strength that adheres the individual fibers together in the paper matrix. Inherent fiber strength is related to the length of the carbohydrate polymers, also known as the degree of polymerization (DP). Average DP (DP) is inferred by performing pulp viscosity measurements. Under certain circumstances during kraft pulping and bleaching, the average polymer lengths can be shortened, resulting in lower pulp viscosity, and may indicate fiber damage. Fiber damage typically manifests itself as a reduction in tear strength for well-bonded handsheets.This paper will review the literature on how pulp viscosity can predict paper/fiber strength and how it can be used as a diagnostic tool. It can be a means to monitor pulp quality during pulping and bleaching, as well as to alert when such operations approach a critical threshold. However, viscosity losses must be carefully and judiciously analyzed. Like most diagnostic tools, viscosity measurements can be misused and abused, which can lead to incorrect inferences about intrinsic fiber strength. This review will also cover these misuses. The overall goal is to provide the papermaker a better understanding of what pulp viscosity is, how it correlates to potential sheet strength, and what its limitations are. It will be illustrated that when pulp viscosity drops below a critical value, it will indicate an appreciable deterioration in the paper’s tear and tensile strength.

ABB’s New R&D Center: Perfect Location for the Transformation of the Pulp and Paper Industry, Paper360º September/October 2023

If Itâ??s "Broke," Fix it With Coagulants, Solutions!, August 2005, Vol. 88(8) (196KB)

If It’s "Broke," Fix it With Coagulants, Solutions!, August 2005, Vol. 88(8) (196KB)

Improving Fiber Yield with Borate Autocausticizing, Solutions!, April 2005, Vol. 88(4) (88KB)

Improving Fiber Yield with Borate Autocausticizing, Solutions!, April 2005, Vol. 88(4) (88KB)

VIEWPOINT: Whereâ??s Our Summer Vacation?, Solutions!, August 2005, Vol. 88(8)

VIEWPOINT: Where’s Our Summer Vacation?, Solutions!, August 2005, Vol. 88(8)

Paper Expo Hits Mill Country

Paper Expo Hits Mill Country

The Basics: What You Need to Know About Dryer Fabrics, Solutions!, October 2005, Vol. 88(10)

The Basics: What You Need to Know About Dryer Fabrics, Solutions!, October 2005, Vol. 88(10) (824 KB)

Teaching paper science to a non-technical audience, Solutions!, March 2004, Vol. 87(3) (59KB)

Teaching paper science to a non-technical audience, Solutions!, March 2004, Vol. 87(3) (59KB)

Energy Management: Doing More With Less, Solutions!, September 2005, Vol. 88(9) (168 KB)

Energy Management: Doing More With Less, Solutions!, September 2005, Vol. 88(9) (168 KB)