Agro-based materials

The increased importance of renewable resources for raw materials and recyclability or biodegradability of the material at the end of its useful life is demanding a shift from petroleum-based synthetics to agro-based materials in industrial applications. Increased social awareness of environmental problems posed by the non-degradable, non-recyclable content of their products is forcing manufacturers to enhance the biodegradable content, which in turn favors a switch to biomaterials [1]. 

In general, such agro-based materials are only used as feed for livestock and not as load bearing materials. Therefore, grass reinforced composites have an excellent potential to be used as fibers. There are plenty of grass resources. Elephant grass-based biocomposites are of interest for automotive applications. 

Current reviews on biosorption are related to general approaches90-93 to diverse types of biomass such as microbial biomass, plant wastes, and agro-based waste materials, or to a specific metal.4-94-98 However, a review on metal biosorption using macrophytes biomass is not available. In this chapter, a review on the current knowledge of biosorption using preferentially nonliving biomass from aquatic plants is presented. 

Demirbas, A., Heavy metal adsorption onto agro-based waste materials A review, Journal of Hazardous Material, 157, 220-229, 2008. 

The agro-based composites industry has an opportunity to follow this trend and greatly expand markets for new materials based on blends and alloys with other materials. Most of the research going on today is focused on agrofiber/plastic-compatibilized blends in an attempt to produce materials with consistent, uniform, continuous, predictable, and reproducible properties. 

The bonding of a hydrophilic agro-based fiber to hydrophobic thermoplastic in such a way as to achieve a synergistic effect (i.e., the best of the properties of each material translated into the composite material) requires compatibiliza-tion of the two phases. It is therefore extremely important to understand the properties of the fiber-matrix interphase and interface. 

Any prospect for sucrose (or any other agro-based chemical) as an organic raw material is based on its sustainable supply and long-term availability. 

There is a wide variety of agro-based or natural fibres to consider for utilization. They can be subdivided based on their origin, viz. vegetable, animal or minerals. Cellulose as a material is used by the natural world in the construction of plants and trees, and by man to make shipping sails, ropes and clothes, to give but a few examples. It is also the major constituent of paper and further processing can be performed to make cellophane and rayon. Depending on the part of the plant from which they are taken, cellulose fibres can be classified as ... 

Heat processing of agro-polymer-based materials like cellulose using techniques usually apphed for synthetic thermoplastic polymers such as extrusion, injection, molding, etc., is more cost effective. This process is often used for making flexible films... 

The use of natural fiber reinforcements in recycled thermoplastic polymers has generated considerable research interest due to the increasing environmental threat created by the high consumption rate of petroleum-based plastics. Therefore, there is a growing interest in the development of green, environmentally-friendly composites for agro-based structural materials. Apart from this, the renewed interests in recyclability and environmental sustainability have also arisen in the last few years. The best possible way to develop such composites are to incorporate natural fibers into recycled... 

Figure 7.11 Tensile strength versus elongation at break for a variety of starch based agro-polymers. N. Follain, C. Joly, P. Dole and C. Bliard Mechanical properties of starch-based materials. I. Short review and complementary experimental analysis. Journal of Applied Polymer Science, 2005, 97(5), 1783-1794. Copyright John Wiley and Sons. Reproduced with permission.

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