Lignocellulosic fiber

Fibers for commercial and domestic use are broadly classified as natural or synthetic. The natural fibers are vegetable, animal, or mineral ia origin. Vegetable fibers, as the name implies, are derived from plants. The principal chemical component ia plants is cellulose, and therefore they are also referred to as ceUulosic fibers. The fibers are usually bound by a natural phenoHc polymer, lignin, which also is frequentiy present ia the cell wall of the fiber thus vegetable fibers are also often referred to as lignocellulosic fibers, except for cotton which does not contain lignin. 

Holzfaser, /. wood fiber, ligneous fiber wood pulp = Holzfaserstoff. -papier, n. wood-pulp paper, -stoff, m. lignin cellulose lignocellulose. 

Attempts have been also made to use ceric ion initiation for grafting vinyl monomers onto lignocellulosic fibers. Lin et al. [27] grafted MMA and AN onto bambo. 

Among lignocellulosic panel products, fiberboard (called fiber insulation board in earlier decades) seems to have caused more fires than the denser products hardboard, particleboard, and plywood. Fiberboard self-heats more because it conducts less of the generated heat out of the... 

Thermodynamically controlled self-assembly of an equilibrated ensemble of POMs with [AlVWnO40]6 as the main component could act as a catalyst for the selective delignification of wood (lignocellulose) fibers (Figure 13.2) [55], Equilibration reactions typical of POMs kept the pH of the system near 7 during the catalysis that avoided acid or base degradation of cellulose. 

Various solvents are being investigated to dissolve lignocellulosic materials. Some approaches focus on the selective depolymerization and extraction of lignin and hemicellulose as pre-treatment to produce clean cellulose fibers for subsequent fermentation or for pulping. Other approaches attempt to dissolve the whole lignocellulose with or without depolymerization. The liquefaction processes that are carried out at high temperature (>300 °C), and produce a complex oil mixture, are discussed above with the pyrolysis processes. 

Chen, R. and Kokta, B.V. (1982). Graft copolymerisation of lignosulphonate with methacrylic acid and acrylate monomers. In Graft Polymerisation of Lignocellulosic Fibers, Hon, D.N.S. (Ed.). ACS Symposium Series, 187, pp. 285-299. 

Gomez-Bueso, J., Westin, M., Torgilsson, R., Olesen, P.O. and Simonson, R. (2000). Composites made from acetylated lignocellulosic fibers of different origin. Part I. Properties of dry-formed fiber boards. Holz als Roh- und Werkstoff, 58(1-2), 9-14. 

Rowell, R.M. and Rowell, J.S. (1989). Moisture sorption properties of acetylated lignocellulosic fibers. In Cellulose and Wood Chemistry and Technology, Proceedings of the 10th Cellulose Conference, Schuerch, C. (Ed.). John Wiley Sons, Inc., New York, pp. 343-355. 

Rowell, R.M., Cleary, B.A., Rowell, J.S., Clemons, C. and Young, R.A. (1993b). Results of chemical modification of lignocellulosic fibers for use in composites. In Wood Fiber/Polymer Composites Fundamental Concepts, Processes, and Material Options, Wolcott, M.P. (Ed.). Eorest Products Society, Madison, Wiseconsin, USA, pp. 121-127. 

Chemical Modification of Lignocellulosic Fibers To Produce High-Performance Composites... 

Table I shows the equilibrium moisture content (EMC) of several lignocellulosic materials at 65 percent relative humidity (RH). Reduction in EMC at 65 percent RH of acetylated fiber referenced to unacetylated fiber plotted as a function of the bonded acetyl content is a straight line (Fig. 2). Although the points shown in Figure 2 come from many different lignocellulosic materials, they...

We are in the process of producing fiberboards from various types of acetylated lignocellulosic fibers. Most of our research has been on pine or aspen particleboards or flakeboards, so the data presented here on dimensional stability and biological resistance come mainly from these types of boards. 

Composites made from lignocellulosic materials have been restricted from many markets because of their moisture sorption, dimensional instability, and to a lesser extent, biological degradation. These negative properties can be overcome, allowing flakes, particles, and fiber from wood and agricultural residues to find markets related to high-performance composites. 

For some applications, a combination of materials may be required to achieve a composite with the desired properties and performance. Property-improved lignocellulosic fibers can be combined with materials such as metal, glass, plastic, natural polymers, and synthetic fiber to yield a new generation of composite materials. New composites will be developed that utilize the unique properties obtainable by combining many different materials. This trend will increase significantly in the future. 

Recent work by the USDA and Kcnaf International (Texas) has demonstrated the potential of both growing and processing kcnaf fibers for newsprinl and other paper products in the United States. Another promising potential use for vegetable fibers is in the new lignocellulosic-hased composites under development in various parts of the industrialized world. Such products are already utilized in the automotive industry for automobile interior door and head liners and as trunk liners. 

Recent studies have proven ethanol to be an ideal liquid fuel for transportation and renewable lignocellulosic biomass to be an attractive feedstock for ethanol fuel production by fermentation (1,2). The major fermentable sugars from hydrolysis of lignocellulosic biomass, such as rice and wheat straw, sugarcane bagasse, corn stover, corn fiber, softwood, hardwood, and grasses, are D-glucose and D-xylose except that softwood... 

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