Biofibers

These biodegradable polyesters are obtained by synthesis from monomers obtained from biomass. Their best example is polylactic acid [PLA) derived from corn. PLA shares some similarities with commodity polymers such as polyethylene terephthalate (PET). It has many good characteristics like good transparency, glossy appearance, high rigidity, and ability to tolerate various types of processing conditions. While PLA has similar mechanical properties to traditional polymers, the thermal properties are not attractive due to low Tg of 60°C [5]. 

Biofibers are classified according to the part of the plant they are extracted from. Some fibers, like cotton, are part of the seeds of plants. Some fibers, like hemp and flax, are contained within the tissues of the stems of plants and referred to as bast fibers. Some fibers, like sisal and banana, are part of the leaves of plants. Some fibers, like coconut, are part of the fruit of plants. Biofibers most commonly used as reinforcements in composites are shown in Table 10.2. 

Bast [stem) fibers Flax, Hemp [and Sunhemp), Kenaf, Jute, Mesta, Ramie, Urena, Roselle, Papyrus, Cordia, Indian Malow, Nettle 

Leaf fibers Pineapple, Banana, Sisal, Pine, Abaca (Manila hemp), Curaua, Agaves, Cabuja, Henequen, Date-palm, African palm. Raffia, New Zealand flax, Isora 

Seed [hairs] fibers Cotton, Kapok, Coir, Baobab, Milkweed 

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Cellulosic fiber reinforced polymeric composites find applications in many fields ranging from the construction industry to the automotive industry. The reinforcing efficiency of natural fiber is related to the namre of cellulose and its crystallinity. The main components of natural fibers are cellulose (a-cellulose), hemicelluloses, lignin, pectins, and waxes. For example, biopolymers or synthetic polymers reinforced with natural or biofibers (termed biocomposites) are a viable alternative to glass fiber composites. The term biocomposite is now being applied to a staggering range of materials derived wholly or in part from renewable biomass resources [23]. 

Low cost biofibers such as jute, sisal, hemp, flax, ramie, banana, coir, etc., have received considerable attention in the recent years. These materials have successfully replaced the synthetic fibers glass in particular and other mineral fillers for fabrication of biobased composites used for engineering applications in various sectors such as aerospace, automobile, electronics, packaging, construction, etc. 

Biofibers can be effectively reinforced within the polymeric matrices in different ways to achieve desired properties such as strength, stiffness, low density, and sound damping, along with eco-friendly characteristics and texture in the composites. The use of biofibers for various commercial applications originated back in the 1990 s. Owing to low prices and the steadily rising performance of technical and standard plastics, the application of these fibers... 

This chapter will focus on the application of these biofibers in the area of biobased composites. Also, a clear presentation of various examples of biobased composites, their properties and characterization studies are reported in the discussion. 

Biopolymers Biomedical and Environmental Applications Table 9.1 Comparative properties of biofibers and conventional man-made fibers [9],... 

The relationship between the strength of the biofibers with the microfibrillar angle and cellulose content is given in the following equation ... 

Gatenholm et al. [23] studied the nature of adhesion in the composites of modified cellulose fibers and pol)q>ropylene. Biofibers were surface-modified... 

Biofiber reinforced hybrid composites have been the major subject of research in recent years. Most published reports limited to the hybrid composite consist... 

Degradation and Flammability Behavior of Biofiber Composites and Biofiber/Glass Fiber Reinforced Polypropylene Hybrid Composites... 

The work presented in this chapter shows a great deal of promise regarding the use of biofiber and its hybrid composites. A number of new avenues for future research are also suggested by the studies presented. 

Controlled biodegradability after effective use is another important factor in favor of biofiber composite. Life cycle analysis of these products can be carried out to evaluate the durability and consistency of these products for various engineering applications. 

Chapters cover nearly every conceivable topic related to polysaccharides, such as biofibers, bioplastics, biocomposites, natural rubbers, proteins, gums, and bacterial polymers. Given the global context it does not seem preposterous to consider the materials discussed as the polymers of the future. 

Yet in practice, the boundary between the two classes is not quite so clear, because different combinations of these materials are possible. Indeed, we can veiy easily combine a cellulose biomatrix with biofibers of cellulose [SOY 09], biofillers with a recycled matrix [ADH 08], recycled fillers with a recycled matrix [ZRI07], or two or more recycled matrices with one another [GRI05]. All these combinations of ecoplastics may potentially be advantageous, but cioss-bio/recycled solutions pose the problem of choosing their end-of-life scenario recycling or composting, or finally incineration ... 

Mohanty, A. K., Misra, M., and Hinrichsen, G. (2000). Biofibers, biodegradable polymers and biocomposites an overview. 

Mechanical Performance of Eulaliopsis binata Biofiber-Based Green Composites... 

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