Origin of plastics polymers

The main characteristic of polymers is, that they are composed of extremely large molecules their molecular mass ranges from 10.000 to more than 1.000.000 g/mol, in contradiction to normal low-molecular substances, which in general are in the order of 100 g/mol (water 18, sugar 342). Polymer molecules are often long, threadlike chains, which are sometimes branched, sometimes chemically cross-linked with each other so that they form a network. 

Polymers are abundantly present in nature, in vegetable and animal tissues (mainly as cellulose and proteins). Several technically used polymers have a natural origin they are being used as technical materials as they are harvested from natural materials ( natural polymers ). 

Other polymers are partly from a natural origin the chain molecule has grown in a living tissue, but has been chemically modified into a half-synthetic polymer . 

A growing number of polymers is wholly synthetic, the chain molecule or the network is being built up from small molecules (monomers) in a chemical process. Some examples of these categories are given below  

These are synthesized from low-molecular components, mostly organic monomers. Most of the monomers are prepared from fossil fuels here we can distinguish between two main categories  

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