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The desire to make more biobased and lower-cost bonded wood products has led to an interest in replacing some phenol and formaldehyde in wood adhesives with soybean flour. Improved knowledge of the soy protein properties is needed to relate resin chemistry to resin performance before and after wood bonding. To expose the soy protein’s functional groups, it needs to be disrupted, with minimal hydrolysis, to maximize its incorporation into the final polymerized adhesive lattice. The best conditions for alkali soy protein disruption were to maintain the temperature below 100°C and react the...

For normally distributed populations, we obtain confidence bounds on a ratio of two coefficients of variation, provide a test for the equality of k coefficients of variation, and provide confidence bounds on a coefficient of variation shared by k populations.

Water-base pressure sensitive adhesives dominate the market of adhesives applied to paper. These materials are formulated as emulsions of acrylic polymers in water. Surfactants are used to stabilize the hydrophobic polymer particles. When water-based adhesives are dried, particles coalesce and surfactant segregates to interparticle domains that provide pathways for water to enter the adhesive film. Atomic force microscopy, under humidity controlled conditions, has been used to characterize formation of these structures in adhesive films. Surfactant rich domains, which strongly interact...

The measurement of effective residual ink concentration (ERIC) in recycled papers is prone to errors. TAPPI Provisional Method T 567 pm-97 is based on application of the Kubelka Munk (KM) theory to diffuse reflection from papers measured once with the black backing and again with a thick backing of the same papers. At high opacities the two results become indistinguishable, leading to an undetermined value for ERIC when the full KM theory is applied. This is handled by use of an approximate value for the KM scattering coefficient to remove the ambiguity. However, the approximate value may...

Acid pretreatment of wood provides significant energy savings during refining but reduces the brightness of the pulp. Acid treatments also extract carbohydrates from wood. Addition of an acid pretreatment process to a thermomechanical pulping process therefore offers an opportunity to reduce refining energy cost and provide a secondary product from a fermentation ethanol plant. A process being investigated by BioPulping International and the Forest Products Laboratory involves pretreatment with oxalic acid or diethyl oxalate and offers 25% or more reduction in specific refiner energy...

Within the past 15 years, at least three bleach plants in North America experienced catastrophic equipment failures associated with the use of 50 wt% peroxide. People were badly injured in two instances, and these mills were fortunate to have avoided fatalities in these events. Hydrogen peroxide can be and has been used safely for many years, but like any strong oxidant, it must be handled with respect. This paper evaluates safety concerns associated with the use of hydrogen peroxide in the bleach plant. Several safety practices are suggested to address issues identified by these explosions...

The density gradient column method was used to determine the effects of uniform and non-uniform pulping processes on variation in individual fiber lignin concentrations of the resulting pulps. A density gradient column uses solvents of different densities and a mixing process to produce a column of liquid with a smooth transition from higher density at the bottom to lower density at the top. Properly prepared pulp fibers float in the column, stabilizing at the level where the mixed solvent density equals the density of the fiber. Because lignin is the lowest density component of pulp...

Strategic identification and local placement of fuel treatments are significant regional and local forest management problems addressed by two tools developed by Forest Service Research and Development.

Overall in the UNECE region in 2006, paper and paperboard consumption, production and trade continued growing, with gains in Europe and the CIS, but a downturn in North America. North American pulp and paper production and consumption decreased slightly in 2006 and early 2007, in part due to the slowdown in United States housing construction and its subsequent economic impacts. Russia’s exports of paper, paperboard and woodpulp fell slightly in 2006, while domestic consumption accelerated by 11%. North American prices of many major pulp, paper and paperboard commodities were approaching...

A bridge consisting of three 6.7-m spans with a stress-laminated deck was constructed in 1991 in the Spirit Creek State Forest near Augusta, Georgia. The bridge was constructed by the Georgia Forestry Commission, with guidance from the U.S. Department of Agriculture, Forest Service, Forest Products Laboratory (FPL). Water-borne chromated copper arsenate lumber was used for the deck, instead of the oil-borne preservatives recommended by AASHTO. The bridge was initially monitored by FPL and remained in service from 1994 to 2001 with no maintenance, at which time the bridge was inspected and...