Materials Science/Materials/Polymers

Polymers
Polymer is a group of substances that has large molecules consisting of at least five repeated chemical units bonded together with a same type of linkage, like beads on a string.Polymer usually contains more than five repeated units and some polymers contain hundreds or thousands of monomers in each of their polymer chains. Polymer materials can be natural or synthetic. Polymer material is a large group of materials whereby they can be further classified specifically into plastics, elastomers and composites!

Sections: 1.	Polymer molecules - mers, chemistry, common polymers 2.	Molecular weight 3.	Molecular structure and configuration 4.	Thermoplastics and thermosets 5.	Crystallinity

1a. Some Basic Terminology
Because polymers are so much larger than other molecules, they are often known as macromolecules. A mer is a repeating unit that makes up a polymer. The term comes from the Greek word "Meros" meaning part. From this, the term polymer was created to mean many mers. The term "Monomer" is sometimes used to refer to the component molecules a polymer is created (synthesized) from.

2. Molecular Weight
The formula for molecular weight of a polymer is

M_n=[sigma]X_i M_i