Composites are attractive materials that consist of two (or more) distinct constitu­ents, which when coupled together provides a material with completely different properties from those of the individual original components.1 Composite materials

are unique because they combine material properties in the manner not existing in nature. Such combination often results in lightweight materials with high stiffness and tailored properties for specific applications.2 Glass fiber is the most dominant fiber and is generally used in 95% of cases to reinforce thermoplastic and thermoset composites. Recent research developments manifested that in certain composite ap­plications, natural fibers demonstrate competitive performance to glass fibers.2 The most widely used composite in industries today is glass fiber-reinforced compos­ite. Although glass fiber composite has numerous advantages, it also has demerits. Glass fiber can cause irritation to the skin, eyes and upper respiratory tract. These inherent health hazards of glass fiber has fuel the extensive search for safer, cheaper and maybe better fiber than glass fiber.3,7 Natural fibers are highly potential alterna­tives for glass fibers. Natural fibers are less abrasive to tooling and not causing as many respiratory problems for workers or consumers. Moreover, they are low cost and have loading bearing potential. Therefore, the use of natural fiber based com­posites has extended to various sectors, such as aircraft, construction, automotive, etc. (Fig. 9.1).8

Biodegradable composite types are not strange materials to human civilization. Their use dates to antiquity, such as the Great Wall of China whose construction

started initially in 121 B. C. as earth works were connected and made strong by clay bricks made of local materials initially using red willow reeds and twigs with gravel during the Han dynasty (209 B. C.). The Wall was later built with clay, stone, wil­low branches, reeds, and sand during the Qin dynasty (221-206 B. C.).8,10 However, biocomposite materials have transited through significant developments in terms of using different raw materials, processes and even applications. The history of fiber — reinforced plastics began since 1908 with cellulose fiber in phenolics, later extend to urea and melamine and reaching commodity status with glass fiber reinforced plastics. The fiber reinforced composites industry is now a multibillion-dollar busi­ness.11

Biocomposites are broadly defined as composite materials made from natural fiber and petroleum derived nonbiodegradable polymers (i. e., PP, PE) or biodegrad­able polymers (PLA, PHA). The latter category of biocomposites which are derived from natural fiber and biobased polymers (bioplastic/biopolymer) are likely to be more environmental friendly and such composites are termed as green composites (Fig. 9.2) (John and Thomas, 2008).11