Green Nanostructured Biodegradable MaterialsConventional disposable packaging items such as containers, trays, plates, bowls, and others, are commonly made from polystyrene or other synthetic hydrophobic plastics and also from paper or paperboard coated commonly with polyethylene. These materials are durable, moisture-resistant and grease-resistant. The disposable items are produced by the industry in great quantities and are relatively inexpensive. After usage, these biostable goods are discarded in the environment and therefore create serious ecological problems. Packaging waste forms a significant part of municipal solid waste and has caused increasing environmental concerns, resulting in a strengthening of various regulations aimed at reducing the amounts generated. Plastic waste imposes negative externalities such as greenhouse gas emissions or ecological damage. It is usually non-biodegradable and therefore can remain as waste in the environment for a very long time; it may pose risks to human health and the environment; in some cases, it can be difficult to reuse and/or recycle. The expected lifetime of polystyrene materials, for example, is several hundred years. Recycling of plastic items is an expensive process. Moreover, in some countries the recycled plastics are prohibited as a material for production packaging for food.
Among other materials, a wide range of oil-based polymers is currently used in packaging applications. These are virtually all non-biodegradable, and some are difficult to recycle or reuse due to being complex composites having varying levels of contamination. Read more (doc)
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