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Sustainable development definition according to the current understanding of European Union is a development that meets the needs of the present without compromising the ability of future generations to meet their own needs. Sustainable if development thus comprises three elements - economic, social and environmental - which have to be considered in equal measure at the political level. The strategy for sustainable development, adopted in 2001 and amended in 2005, is complemented inter alia (among other things) by the principle of integrating environmental concerns with European policies which impact on the environment.
Due to the fact that there is a lot of misleading information about green plastics, standardization organizations developed standards for the field of bioplastics. In the middle of 1990 European Commission ordered CEN (European Committee for Standardization) to develop standards for compostable packaging. The result of this work is the standard specification .EN 13432:2000 which is harmonized with the Directive 34/62/EC concerning packaging.
Before moving on to the definition and classifications of plastics, we have to understand the building blocks of plastics. Those are called polymers. In short polymers are large molecules made of repetitive units called monomers. They could have linear, branched or cross-linked structure. Linear polymers are often thermoplastic, that is to say they "are fusible in certain temperatures and also soluble in some solvents. Cross-linked polymers are infusible and insoluble. Polymers are widespread in nature. They are building material for plant and animal organisms. Starch, cellulose, proteins and chitin are all polymers. Other large group of polymers are synthetically made from petrochemical sources, natural gas and coal. All polymer groups are used in many industrial branches.
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