Wood products industry

In 1991, timber-related secondary products manufacturing industries added an estimated 40,128 million of value to primary timber products (Table 11). Most of the timber-related value added (63%) originated in the paper and aUied products industry. The lumber and wood products industry added nearly 37% of total timber-related value added. Less than 1% was from chemicals and aUied products. 

Sulfur dioxide reduction to achieve required emission levels may be accomplished by switching to lower-sulfur fuels. Use of low-sulfur coal or oil, or even biomass such as wood residue as a fuel, may be less expensive than installing an SO2 control system after the process. This is particularly true in the wood products industry, where wood residue is often available at a relatively low cost. 

While discussing ethers we should mention that the presence of unreacted anisoles or methyl anisoles is highly undesirable in the manufacture of phenol-formaldehyde resoles. These materials tend to be unreactive relative to phenol under normal resole conditions. They are also volatile and have odors detectable at very low concentrations. They have been the source of worker complaints and costly claims in the wood products industry. Benzophenones and methyl phenyl ketones are also common phenol contaminants that are problematic in this regard. 

Phenolic-neoprene contact cements are used for structural metal-metal bonding. especially where fatigue resistance and low temperature performance are important [209]. They are also used for bonding textiles, wood, rubbers, plastics, ceramics, and glass to metal and to one another. Solvent toxicity and flammability has greatly reduced the use of contact cements in the wood products industry. Water-based contact cements persist, but generally do not perform as well as the solvent systems, thus allowing market erosion by alternative binders. 

After organizing the aforementioned program, which employed a number of graduate students and postdoctoral fellows, Fred decided to accept a job with the Weyerhaeuser Company in Seattle, Washington. At Weyerhaeuser, Fred was assigned to one of the most difficult problems of the wood-products industry, namely, development of a practical and economic... 

Tihe preparation and properties of cellulose graft copolymers have A been of considerable interest in the textile, paper, and wood products industries for a number of years. Both free radical- and ionic-initiated graft copolymerization reactions of vinyl monomers with cellulose have been reported. The vinyl-cellulose copolymers have some of the properties of both the cellulosic fibers and the grafted polyvinyl copolymers (I, 3, 47). 

Thus, the picture emerges of a multifaceted wood products industry founded largely on natural adhesives but successfully weaned onto synthetic resins by a combination of low material costs and formerly unattainable performance properties. As a result of this improved performance, the development of other useful bonded wood products was heavily stimulated. 

In view of these suggestions and examples, it is evident that the wood products industry retains its faith in natural adhesives and their capabilities even in this era of synthetics. It is likely that the industry will continue to turn to them without restraint as their price or performance dictates. The desire, of course, is to keep the various wood-bonding operations functioning as efficiently as free market conditions and competitive innovation will permit. 

Since shutdown represents a clear loss both to the producer and the public, there is an expressed willingness within the wood products industry to accept (even if reluctantly) considerable production change in the interests of continued operation. From this industry position, the message to adhesive scientists seems clear and supportive although perhaps indirect. Namely ... 

Finally, for those adhesive developments based on renewable resources that are immediately competitive and/or unique in performance, the wood products industry will do its share to assist with their evaluation and use. Commercial guidance toward this end will be freely provided. 

These thoughts and suggestions are industrially oriented, to be sure. They arise from practical need and reflect concern for future adhesive supply. Collectively, the various forms of wood utilization represent an extremely large and diverse market for adhesives, probably the largest in the world today. Thus, industrial comments seem appropriate. Apart from identified needs, however, the wood products industry recognizes the value of research into the chemical structure and adhesive mechanisms of natural polymers unrelated to current problems. The next echelon of technical development can be expected to arise from this research. It is also acknowledged that certain of the adhesive performance characteristics requested cannot be accomplished with the current level of scientific information. Finally, it is the wood products industry s view that natural adhesives and resources will inevitably play an important part in its future. Thus, they represent a significant and potentially productive area for current adhesive research. 

Adhesives made from blood and casein were some of the first used in the wood products industry. They have been replaced in many applications by petroleum-based adhesives, which show improved performance or better economics. Despite this competition, they remain important in certain specialty areas due to their unique curing and bonding characteristics. 

Robinson CF, Petersen M, Sieber WK, et al. 1996. Mortality of carpenters union members employed in the US construction or wood products industries, 1987-1990. Am J Ind Med 30 674-694. 

These are briefly reviewed, followed by summary economics for the production from wood of electricity, steam, and cogenerated products intermediate-Btu gas (IBG) and substitute natural gas (SNG) methanol ammonia fuel oil and pyrolytic oil and char. Several processing steps in these conversion schemes are conceptual or are at early stages of development by DOE, EPRI, GRI, and others (an exception would be wood steam/electric power plants, which are commercially used by the electric utility and wood products industries). Consequently, the economics presented here may generally tend to be optimistic. Additional details of the analyses can be found in Kohan and Barkhordar(1) Jones, Kohan and Semrau(2J and Kohan and Dickenson( 3). ... 

R. JAMES Oamie) BARBOUR is a wood scientist with Forintek Canada Corporation s eastern laboratory in Ottawa, Ontario, Canada. His research involves the evaluation of wood quality problems encountered by the Canadian wood products industry in the processing of the existing resource, as well as those expected in the utilization of the managed resource that is currently being grown. 

Mill residue is a source of wood waste which can be derived from the wood products industry. Depending on the efficiency of a mill, up to fifty percent of the incoming material can become waste material in the form of bark, sawdust, cut slabs, etc. (4). This residue is an excellent source of fuel however, for a long-term supply, it may dwindle as more emphasis is placed on utilizing it for "in-house" energy uses by the wood products industries. 

Hoff, E. "Abstracts of Papers , the Conference on Energy and the Wood Products Industry sponsored by the Forest Products Research Society. Atlanta. Ga., 1976. 

Solvent eontaining formaldehyde resin paints and laequers have been used extensively in Nordie furniture and wood product industry. In flie early 1980 s, eombined solvent concentration and especially formaldehyde levels often exeeeded the OELs. The OEL violations became rare in the late 1980 s. The recent concentrations of other solvents than ethanol (even its mean eoneentration was only 17 ppm) have been below 10 ppm in Finland. Nowadays, solventless acrylics are mainly used for industrial wood coatings. This substitution has, however, ereated a new occupational health problem. The new products have eaused many eases of dermal sensitization among exposed workers. 

The use of condensation resins [1,2] for bonding wood components like veneers, particles, or fibers plays a dominant role in the wood products industry. Though mechanical interlocking is not the main reason for bonding, still an adequate penetration of the resin into the wood surface enables formation of an enlarged bonding interface this penetration must take place before curing of the resin has occurred. 

Oriented Strandboard (OSB). Oriented strandboard (OSB) panels have been developed as an alternative to plywood in building construction. The emergence of OSB was driven in part by a decreased supply of large diameter logs suitable for veneer production, and by innovation and productivity changes in the North American wood products industry over the past few decades as well as the structural performance of OSB products, which are suitable for use in most plywood applications but at a much lower cost. In addition, OSB manufacture allows small, low grade timber resources to be processed into a marketable product. This effectively saves raw materials that are in short supply and promotes efficient utilization of wood (3,5,6). 

Most of the recent efforts to develop uses for the condensed tannins have centered on their application in wood adhesives. Reviews by Pizzi (182, 186) and others (15, 78, 87, 93, 208) provide references to several hundred papers and patents on this subject. Despite world-wide research efforts on other sources of tannins, particularly since the 1972-1973 petroleum shortage, the mimosa or wattle tannins extracted from the bark of black wattle Acacia mearnsii) remain the major source of condensed tannins exploited commercially for adhesive manufacture. Of the approximately 100000 tons of wattle tannin produced annually, only about 10000 tons are used in wood adhesives, predominantly in South Africa but also in Australia and New Zealand (186). The extensive use of wattle tannins by the wood products industry of South Africa is impressive indeed, as these tannins have partly replaced phenol and resorcinol usage in adhesives for bonding of particleboard, plywood, and laminated timbers (182, 186, 213). Three factors have contributed to the success in use of wattle tannin-based adhesives, namely the comparatively high costs of phenol and resorcinol in the Southern Hemisphere, their resorcinolic functionality and low molecular weight and, perhaps most importantly, the commitment by the research and industrial communities of these countries to reduce the reliance of the forest products industry on petroleum-based adhesives. 

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