Effects of Loblolly Pine Tree Age and Wood Properties on Linerboard Grade Pulp Yield and Sheet Properties. Part 2: Effects on Sheet Properties

摘要

This paper reports the results of a study of relationships of loblolly pine tree age and wood characteristics with the properties of pulp obtained when the trees were chipped and pulped by the kraft process. Eighteen 13-year old and eighteen 22-year-old loblolly pine trees were selected to represent specified ranges of specific gravity and lignin content. The trees were further characterized by chemical analysis, near-infrared (NIR) spectroscopy and SilviScan analysis of fiber dimensions and properties before being pulped by the kraft process. Handsheets formed from the resulting pulps were characterized in terms of sheet properties that are important for linerboard grades. Multiple regression analysis was then used to identify wood characteristics that most influenced sheet properties and to derive equations relating sheet properties to tree age, specific gravity and chemical composition. In addition, NIR calibrations were developed to allow prediction of sheet properties from NIR analysis of wood. The results showed that nearly all of the differences in properties of pulps made from 13- and 22-year-old trees can be attributed to differences in fundamental wood properties and that sheet properties can be estimated by measuring their near infrared spectra.