Polymers are derived from the word POLY which means more than one and MER meaning parts.
Polymers are large molecules which make different types of structure like DNA and RNA.
The polymers are classified as Synthetic and Natural polymers.
The polymers are made up of a process known as polymerization which can be imagined as the linking of small molecules known as monomers. The importance of polymers can be viewed as -The proteins which are derived from the food is also a form of the polymer.
Historically the concept of linkage of monomer was first proposed by Hermann Staudinger in 1920.
Coming back to our engineering world, The polymers form an intensive part which increases the tensile strength of a material. For example –Rubber which is a polymer has more tensile strength thus it can bear a high load before fracture.
Thus for a small strain change in length is more in rubber.
Polymers also have an interesting property which is they mix due to entropy not due to energy interaction. Thus free energy is available in a good amount.
Now the applications of the polymers are it is used in the plastic The polymerization and polyaddition results in the making of plastics. Although there are many environmental hazards for plastics.
Polypropylene is a commonly used plastic used in wielding and chemical industries.