Green Chemistry      Jemma Vickery    jv2237@bris.ac.uk

 

  Introduction

    Biodiesel

    Green Solvents

    Ionic Liquids

    Degradable Plastics

    Famous Environmental Disasters

    Glossary

    References

   Introduction

What are plastics made of why does this pose a problem to their degradation?

Prominent modern plastics including polyethylene, polypropylene and polystyrene pose a problem on the environment due to their bioinertness.  This means they take along time to degrade in the environment and the accumulation of plastic litter from agricultural, industrial and commercial sources is posing a serious problem on the environment.  Recent developments of environmentally degradable plastics are providing a highly attractive alternative to non-degradable plastics.

What are Environmentally Degradable Plastics?

Biodegradable plastics are plastics which decompose to water and carbon dioxide by the actions of microorganisms and are safely returned to the natural biosphere as organic carbon.    Biodegradable plastics are derived from non petroleum based commericial wrappings, for example starch-based packaging which can be derived from corn or potatoes.

The table above illustrates the cyclic processes which yield biodegradable plastics from agricultural products and fermentative routes.

Examples of Biodegradable Plastics

Polyhydroxyalkanoate (PHA):  a biodegradable polymer produced by bacteria, which has similar properties to polypropylene.

Polylactide (PLA): a biodegradable polymer which is derived from lactic acid, which can be broken down in our bodies and therefore has valuable biomedical applications.

See references (10).