Vegetable fibers processing

Fiber Analysis. Paper may be composed of one or several types of fibers, eg, animal, vegetable, mineral, and synthetic (see Eibers). Paper is generally composed of woody vegetable fibers obtained from coniferous (softwood) and deciduous (hardwood) trees. QuaUtative and quantitative methods have been developed to determine the fibrous constituents in a sheet of paper (see TAPPI T401). However, the proliferation in the number and types of pulping processes used have made the analysis of paper a much more complex problem. Comprehensive reviews of the methods are given in References 20 and 23. 

Processing aid Petroleum based Synthetic low PCA content oil, vegetable oil Casing Synthetic fiber Vegetable fiber... 

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. 

Up to pressures of 20 bar, the operating temperature and corrosiveness of the process fluid will be the controlling factor in gasket selection. Vegetable fiber and synthetic rubber gaskets can be used at temperatures of up to 100°C. Solid... 

The interested reader is advised to read other reviews of the subject. For instance, Biagiotti, Puglia, and Kenny [27] provide a good comprehensive review of the structure, processing, and properties of vegetable fibers. 

Fibers have been widely used in polymeric composites to improve mechanical properties. Cellulose is the major substance obtained from vegetable fibers, and applications for cellulose fiber-reinforced polymers have again come to the forefront with the focus on renewable raw materials. Hydrophilic cellulose fibers are very compatible with most natural polymers. The reinforcement of starch with ceUulose fibers is a perfect example of a polymer from renewable recourses (PFRR). The reinforcement of polymers using rigid fillers is another common method in the production and processing of polymeric composites. The interest in new nanoscale fillers has rapidly grown in the last two decades, since it was discovered that a nanostructure could be built from a polymer and layered nanoclay. This new nanocomposite showed dramatic improvement in mechanical properties with low filler content. Various starch-based nano-composites have been developed. 

Another strong aspect of vegetable fiber application in the industry is their ecological character with possibility of carbon dioxide reduction from the atmosphere during the fibrous plants cultivation processes. Use of bast fibers ensures biodegradability of the end product, if natural polymer, e.g., PLA is applied as a matrix. 

Natural fibers are those which are already existing in nature and obtainable with different processes, both mechanical and chemical. They can be approximately classified according to their origin vegetable fibers, which are all those natural lig-nocelluloses fibers, animal fibers (wool, silk), and mineral fibers (asbestos). 

Processing temperature of plant fiber composites is restricted to less than 200°C or below as vegetable fibers undergo degradation at higher temperatures. 

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