Some of the most common examples of polymers are plastics and proteins. While plastics are the result of the industrial process, proteins abound in nature and so are usually considered a natural polymer. Actually, if you surveyed the plants and animals that live around you, you would probably find many natural polymers.
Polymers are defined as long molecular chains made from repeating units. Often, polymers are associated with modern plastics and other synthetic compounds, but quite a few polymers occur naturally in nature. Originally, polymers were considered a property of carbon-based molecules, but these kinds of repeating structures can also be found in non-carbon substances, such as silicones. In fact; polymers in both synthetic and natural compounds can become quite long. Today, scientists working on the development of new synthetic products often study some of the more complex examples of natural polymers in an effort to better understand this useful scientific phenomena.
Wood and Potatoes
Polymers can sub-divide into two subgroups, one of which is a polysaccharide. Polysaccharides are so named because their main unit is a sugar molecule, which contains just carbon and hydrogen. From these relatively simple molecular strands, nature has created such polymers as cellulose, starch, DNA, cotton and rubber. Simple and starches are often created by plants through the process of photosynthesis, then linked together to form complex polymers.
Proteins and Enzymes
The other group of polymers is known as polypeptides. In this sub-group of polymers, amino acids are the building block. An amino acid is formed when a single amino (NH2) is joined to a carboxyl group (COOH). Still, it takes at least two amino acid groups to make up one peptide molecule, then two peptides must be joined together to create a polypeptide. Within the polypeptides the possible combinations are enormous, but most proteins and enzymes fall within this large subdivision.
Name any protein or enzyme and most likely you have an example of a natural polymer. Another fascinating example of polypeptides is silk, which is made by the silkworm, but has been a staple part of mankind's apparel for thousands of years. This natural material forms long thin fibers, a very unusual event from a substance based on amino acids. Nylon, a synthetic polyamide, appears in many way to mimic silk, though its molecular structure is slightly different.