Many of the terms, definitions, and concepts used in polymers are not generally found in other branches of science, these need to be understood in order to fully discuss the fundamentals of polymers. Application of polymer composites is increasingly important in many different industries, like aerospace, automotive sectors, and areas dealing with corrosion and construction because they are strong, resistant to damage, and easy to install. The global composites market is expected to reach about $62.6 bn in 2012 (Source: The Composites Market 2012–2022: Glass Fibre, Carbon Fibre and Aramid Fibre report, Visiongain 2012). In addition, applications are also found in fuel cells, sensors, electromagnetic interference shielding, human implants, and scaffolds.
This book chapter highlights both basic fundamentals and advances toward the understanding of properties of polymers and polymer composites holding various aspects. This chapter also deals with basic characteristics of polymers and polymer composites. In addition, current application and future trend in advances of the polymer and its composite will be discussed.

Polymer

The name “polymer” gives an idea of the structure of the materials. The term “polymer” arrived from Greek words in which poly means many and mer means unit. A polymer is a very large molecule formed by successive linking of many monomers into a chain or network structure. The concept of the polymer emerged in the 1920s presented by Hermann Staudinger who received the Nobel Prize in 1953. Generally, a polymer has a chain or network structure made of a carbon backbone with hydrogen. In addition other elements such as O, N, F, Si, S can be arranged on it. Some of the very common polymers are polyethylene (PE), polypropylene (PP), polystyrene (PS), and polyvinylchloride (PVC) (Billmeyer 2007; Fried 1995; Mark and Kroschwitz 1985).

The simple structure of polyethylene, for example can be written as given in Fig. 1.

Monomer

Monomers are generally simple forms of organic molecules which can react and give larger molecules in the form of polymer. Figure 2 shows the monomer structure of different polymers.