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Pine bark, pine pulp, and spruce pulp were reacted with laccase in the presence of phenolic laccase substrates to modify the fiber surface properties. The acid-base and dispersive characteristics of these modified steam-treated thermomechanical loblolly pine pulps were determined by inverse gas chromatography. Different combinations of substrates with laccase modified the Lewis acid-base characteristics of the pulp. The binding of methylene blue was found unsuitable as an indicator of negative charges on pulps modified by laccase with phenolic substrates; however, its binding did indicate...

Annual paper and paperboard output climbed by 2.2% in the EU/EFTA subregion in 2003, a record year for European papermakers, while the subregion’s woodpulp output climbed by 2.8%. Higher paper and paperboard exports from the EU/EFTA subregion to non-UNECE countries, and a 16% increase in net exports in 2003, propelled expansion of output. Paper and paperboard consumption in central and eastern Europe was boosted by stronger regional economic growth in 2003, but the region also experienced a large increase in imports. Consumption of paper and paperboard in the Russian Federation increased...

The purpose of the study was to assess the potential for using red maple sawlogs to manufacture laminated veneer lumber (LVL). The primary objective was to determine the yield of ultrasonically graded veneer from red maple logs. A sample of 48 logs was obtained from six Eastern and Lake States in the United States. The logs were visually graded and shipped to a plywood manufacturing facility in northern Michigan where they were debarked, steamed for 72 hours,and then rotary peeled into nominal 1/8- inch- (standard 3-mm-) thick veneer. Special care was taken to ensure that each veneer sheet...

The objective of this study was to determine the time required to heat the center of red pine boards to various temperatures for sterilization. This information will serve as a guideline for those concerned with heat sterilizing wood pallets and other wood shipping containers to meet heat treatment requirements for protection against invasive pests. Red pine boards, 4 inches (102 mm) wide and 1, 2, and 4 inches (25, 51, and 102 mm) thick, were heated in several combinations of heating temperature and relative humidity. The time required to heat the boards increased exponentially with...

In response to concerns about hardboard siding failures, a study was performed to assess if performance in a current hardboard industry quality assurance test procedure correlated with in-service performance and how well this performance might be predicted by use of alternative or additional test procedures. A variety of laboratory tests were performed on a large number of specimens, and the in-service performance of matched specimens was periodically evaluated over 38 months of outdoor exposure. Siding specimens were installed on two test fences that were sprayed with water for one hour...

Spruce, coconut coir, sugarcane bagasse, kenaf bast, kenaf core, and cotton were tested for their ability to remove copper, nickel and zinc ions from aqueous-solutions as a function of their lignin content. The fibers were analyzed for sugar and lignin content and extracted with diethyl ether, ethyl alcohol. hot water, or 1% sodium hydroxide. The order of lignin content in un-extracted fibers is coconut coir > spruce > kenaf core > bagasse > kenaf bast > cotton. The fiber with the highest level of heavy metal removal was kenaf bast that had a very low level of lignin, showing that removal...

Wood fibers, after thermo-mechanical pulping, have a high concentration of lignin on the outer surface of the fiber; the residual middle lamella of the woody cell wall. When wood fibers are oxidatively treated with a chelator produced by Gloeophyllum trabeum (a brown-rot fungus), in the presence of hydrogen peroxide (H2O2) and ferric iron (FeIII), free radicals are produced. Using a synthetic chelator to mimic the action of the free radical generating system, we applied the system to wood fibers to activate the lignin-rich fiber surface. Activating the lignin and/or extractives on the...

Adhesives can be formulated to facilitate their removal by typical paper recycling unit operations. The investigations described in this paper are focused on determining fundamental properties that control particle size during pulping. While pressure-sensitive adhesives (PSAs) with high elastic moduli tend to survive pulping with larger particles, facestock and adhesive surface properties also play critical roles. We investigated both the effect of wet-strength additives and sizing agents on screen removal efficiency and found that one can shift a recycling-benign adhesive to one that will...

For 1.5 to 2.5 billion people in the world, lack of clean water is a critical issue. It is estimated that by the year 2025 there will be an additional 2.5 billion people who will live in regions already lacking sufficient clean water. In the United States today, it is estimated that 90% of citizens live within 10 mi of a body of contaminated water. Large numbers of point (single, identifiable) and nonpoint sources having low flow volume [50 gal (190 L) per minute or less] contribute significantly to these water contamination problems. These sites pose a major unsolved problem because they...

The crystallization behaviors of polyamide-6 (PA-6) and its nanocomposites undergoing the microcellular injection molding process are studied using Transmission Electron Microscopy (TEM), X-ray Diffractometer (XRD), Polarized Optical Microscopy (POM), and Differential Scanning Calorimetry (DSC). The relationships among the morphology, the mechanical property of the molded parts, and the crystallization behavior are investigated. With the addition of nanoclays in microcellular injection molded parts, the growth of the a -form crystal is suppressed and the formation of g -form crystals is...