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Computational chemistry methods can be used to explore the theoretical chemistry behind reactive systems, to compare the relative chemical reactivity of different systems, and, by extension, to predict the reactivity of new systems. Ongoing research has focused on the reactivity of a wide variety of phenolic compounds with formaldehyde using semi-empirical and ab initio computational chemistry methods. This research has been expanded to study theoretical transition states formed on reacting phenol with formaldehyde. According to transition state theory, the energy of a transition state is...

The Draft RPA Timber Assessment projects, over the next 50 years, the likelihood of increasing abundance of softwoods in the South and decreasing abundance of hardwoods in the South. These trends in supply, along with projected contributions from the North and West, imply U.S. consumption needs could be met without increasing net product imports and would not increase softwood timber prices over the next 50 years. However, under this scenario, the adequacy of timber supplies depends on 1) continued expansion of softwood plantations with increased management intensity in the South, 2)...

Increased use of pressure sensitive adhesives for labels and stamps has introduced another contaminant into the office paper stream: silicone- coated release liners. This study examines methods and conditions for removal of contaminants, including these liners, from a typical batch of discarded office papers. Removal of contaminants contained in the furnish were compared using alkaline and near neutral pH repulping conditions. Residual contaminants were measured by image analysis, and the number and size of the contaminants were compared on handsheets that were prepared from samples...

Phenolic resins are important adhesives used by the forest products industry. The phenolic compounds in these resins are derived primarily from petrochemical sources. Alternate sources of phenolic compounds include tannins, lignins, biomass pyrolysis products, and coal gasification products. Because of variations in their chemical structures, the reactivities of these phenolic compounds with formaldehyde vary in quite subtle ways. A method is needed for predicting the reactivity of phenolic compounds with formaldehyde in order to allow researchers to efficiently choose those compounds that...

Corynocarpaceae group closely with Coriariaceae and Cucurbitaceae by axial parenchyma types (vasicentric scanty plus apotracheal banded plus ray- adjacent, all in strands of 1-2 cells) and Homogeneous Type II rays. Begoniaceae, Datiscaceae s. s., and Tetramelaceae group on the basis of absence of banded axial parenchyma and subdivision of the vasicentric parenchyma into strands of 3-5 cells. All of the families of Cucurbitales (except Anisophylleaceae) have two unusual features: minimal borders on perforation plates and unusually wide multiseriate rays (not accompanied by uniseriate rays)....

Although natural fiber reinforced commodity thermoplastics have a wide range of nonstructural applications in the automotive and decking industries, there have been few reports of cellulosic fiber-reinforced engineering thermoplastics. The commonly held belief has been that the only thermoplastics amenable to natural-fibre reinforcement are limited to low-melting (below 180°C) commodity thermoplastics like polyethylene and polypropylene. However, in three recent papers we have shown that the high-melting engineering plastics, nylon-6 and nylon 66 can indeed be reinforced with cellulosic...

In the mid-1990s, researchers at the Forest Products Laboratory developed a coupling agent, hydroxymethylated resorcinol (HMR), that has the ability to enhance adhesive bonds between wood and nontraditional adhesives (Vick and others 1995, 1996). HMR is also effective in promoting durable bonding of phenol-resorcinol- formaldehyde (PRF) adhesives to CCA-treated Southern Pine (Vick 1995). This presentation reviews progress in development of HMR for use with nontraditional adhesives and for treated wood.

The technology currently exists to manufacture natural fiber thermoplastic composites from recycled materials. Development of commodity-building products from these composites would open up huge markets for waste-based materials in the US. To date, the construction industry has only accepted wood thermoplastic composite lumber (and only for limited applications). In little more than a decade, the use of composite decking has grown to about 4% of the exterior decking market. Even larger markets within the building industry could be developed, such as the roofing market. However, a lack of...

Hybrid poplars are fast-growing, moisture-loving, full-sun-loving large trees that can be a rapid source of wood fiber. With the introduction of waferboard, oriented strandboard (OSB), and laminated strand lumber (LSL), aspen utilization has dramatically increased. Indigenous and hybrid poplars, however, present their own challenges, such as high discoloration potential, difficulty in drying, and high tension wood content. Further research is needed for improved selection of clones to ensure that desirable physical and mechanical qualities of poplar wood are produced for the anticipated...

Antrodia aurantia Lodge, Ryvarden & Perdomo-Sanchez is described as new. It has bright orange resupinate basidiomes that lack rhizomorphs and has pores that are deep, soft, large, and angular to sinuous; it is associated with a brown rot on Pinus occidentalis. A key to all American Antrodia and Diplomitoporus species is provided.