الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Approximately 140 million tones of synthetic polymers are produced worldwide every year. Since polymers are extremely stable, their degradation cycles in the biosphere are unlimited. Environmental pollution by synthetic polymers, such as waste plastics and water soluble synthetic polymers in waste water has been recognized as a major problem. Plastics and polymers are an integrated part of our daily existence. However, because of stability and resistance to degradation, these are accumulated in the environment, at the rate of about 8% by weight and 20% by volume of the landfills (Premraj & Doble, 2005).Polymers are a class of ―giant‖ molecules consisting of discrete building blocks linked together to form long chains. Simple building blocks are called monomers, while more complicated building blocks are sometimes referred to as ‗‗repeat units‘. Biopolymers are defined as polymers formed under natural conditions during the growth cycles of all organisms. Therefore, they are also named natural polymers. They are formed within cells by complex metabolic processes (Leon et al., 2009; Madigan et al., 2001).