Biodegradable plastic

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Biodegradable plastics are plastics that will biodegrade in the natural environment. Biodegradation of plastics can be achieved by enabling microorganisms in the environment to metabolise the molecular structure of plastic films to produce an inert humus-like material that is less harmful to the environment.

The use of bio-active compounds compounded with swelling agents ensure that, when combined with heat and moisture, they expand the plastic's molecular structure and allow the bio-active compounds to metabolise and neutralize the plastic.

1 Advantages of biodegradable plastic
2 Environmental concerns
3 Cost of production
4 See also
5 External links
6 References

[edit] Advantages of biodegradable plastic

Using proprietary formulations with existing processes only nominally effects production costs. This is largely because the technology does not rely on changing to re-engineered plastics which have not achieved economies of scale but merely requires adding a small percentage of bio-active material to existing resins. In addition, the additions do not jeopardize the products' quality. Plastic products making use of this type of technology can be manufactured to be clear or opaque, and in any colour.

[edit] Environmental concerns

Over 200 million tonnes of plastic are manufactured annually around the world, according to the SPE^{[citation needed]}. Of those 200 Million tonnes, 26 Million are manufactured in the United States. The EPA reported in 2003 that only 5.8% of those 26 Million tonnes of plastic waste are recycled. The wastage of plastic at increased rates are causing problems with landfill capacity throughout the world. The use of biodegradable plastic is one means of reducing the volumes of waste produced by modern societies.

[edit] Cost of production

Two articles by T.Gerngross et al. in 1999^[1] and in 2000^[2] would be later widely cited, indicated that the energy required to produce one kilo of polyhydroxyalkanoate (PHA) biopolymer (by fermentation) from plants was equivalent to the consumption of 2.65 kg of fossil fuel while the production of one kilo of polypropylene required only 1.54 kg of fossil fuel ^[3]. These balances include the energy required to produce the feedstock as well as the polymer.

Life cycle assessment data for the production of polyhydroxyalkanoates from sugar cane (Brazil) was not mentioned in these studies. Manufacturing of PHAs by fermentation in Brazil enjoys a favorable energy consumption scheme where bagasse is used as source of renewable energy ^[4] .

Technology to produce PHA is still in development, and energy consumption can also be further reduced by eliminating the fermentation step^[5], or by utilizing food waste as feedstock^[6].

Starch-based biopolymers (produced by various manufacturers) and polylactide (produced by NatureWorks in the US) require less fossil fuel than polymers from non-renewable sources^{[citation needed]}