ABSTRACT
Polymers are substances consisting of large molecules also known as macromolecules. The molecules are built up of many subunits called monomers which are linked together, usually by covalent bonds. In a polymer, the number of subunits is generally larger than 100 [1]. Assemblies of less than 100 subunits are often referred to as oligomers. Macromolecules make up many of the materials in living organisms, as for example cellulose, lignin, proteins and nucleic acids. The latter two have highly specific roles in life. Proteins control many biochemical processes and nucleic acids store genetic information. Many polymers are man-made materials, and are therefore called synthetic polymers. These polymers have a great industrial importance because they offer an attractive compromise between ease of processability and final mechanical and thermal properties. This article focuses on the general properties of polymers, without dealing with the specific roles of natural polymers, such as proteins and nucleic acids.
