Vegetable fibers mechanical properties

Vegetable fiber, glue binder Vulcanized fiber 212 Resists oil and water to 212°F. Low cost, good mechanical properties. Resists gasoline, oils, greases, waxes, many solvents. 

Stout has written a detailed review on jute and kenaf. X-ray diffraction patterns show the basic cellulose crystal structure, although in jute and kenaf the crystalline orientation is high and the degree of lateral order is lower than in flax. Batra" in a comprehensive review has highlighted the morphological structures and physical, mechanical and chemical properties of other long vegetable fibers. 

It has been mentioned earlier that vegetable fibers other than cotton and kapok are multicellular. The mechanical properties of these fibers, therefore, reflect an interaction between their ultimates and their middle lamella substances ramie is an exception because the size of its ultimates is large enough to act as a fiber. 

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. 

Recently, bacterial cellulose, produced by Acetobacter Xylinum, was used as reinforcement in composite materials with a starch thermoplastic matrix [230]. The composites prepared with bacterial cellulose displayed better mechanical properties than those with vegetable cellulose fibers. 

It should be noted, however, that the thermal and mechanical properties of vegetable fiber reinforced polymer composites are notoriously lower than those of similar composites reinforced with synthetic fibers (e.g., carbon, glass, aramid) [1, 2,12]. The above-mentioned techniques, i.e., fiber drying and surface treatment or the addition of a compatibilizer, are mostly not enough to adjust the properties of vegetable fiber reinforced polymers to the desired level. Moreover, even though these treatments enhance adhesion, there is some controversy in the literature about their effect on the mechanical properties of the fiber itself and even when a more pronoxmced gain is noticed after treatment, the improvement for the composite is often within the scatter of the results. In addition, the cost and environmental impact of some of these treatments, especially of those more elaborated, often prevent their industrial scale applications. 

Indeed, a wider use of vegetable fibers in composites replacing synthetic fibers, or more realistically, glass fiber, in either thermoset (mainly unsaturated polyester) or thermoplastic (mainly polyolefins) composites is mainly limited by their comparatively poorer mechanical properties, higher moisture absorption and lower compatibility to... 

As a matter of fact, many authors consider that the behavior of hybrid composites is mainly influenced by the properties of their outer fiber layers, and that optimum mechanical properties can be obtained by placing high strength fibers at the outer layers [71]. However, this is not a general rule, and depending on the external load being applied to the composite, the use of at least one vegetal fiber outer layer can be of interest. 

In addition to conventional vegetal cellulose fibers (Figure 1 A), other forms of cellulose have been assessed in the last few years. The use of micro and nano-cellulose fibers, namely whiskers, obtained from a marine species (Samir, 2005), bacterial cellulose produced by some bacterial strains (Pecoraro, 2008) as well as micro- or nano-fibrillated cellulose prepared by mechanical, enzymatic or chemical treatments of the vegetal fibers (Nakagaito, 2004), for the development of high performance composite materials is attracting researchers from diverse fields (Dufresne, 2008 Lee, 2009), as the addition of very modest amounts of nano fibers leads to new composite materials with superior mechanical properties and new functionalities (Klemm, 2009) when compared with their conventional cellulose fibers counterparts. 

Vegetable Oils commercially available 15-25 9 Resistant little or no change in weight small effect on mechanical properties generally suitable for practical use Ketron PEEK GE-30 Quadrant EPP Filler 30% Glass fiber... 

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