Material Science and Metallurgy

11

Organic Materials

11.1 INTRODUCTION

Plastics are generally referred to as polymeric material. ‘Poly’ stands for many and ‘mer’ stands for parts, so polymer is an organic material with repeating molecular units (called mer) that can be formed into usable solid shapes by casting, sintering or melt processing. As ethylene consists of two carbon atoms and four hydrogen atoms and polymer has n degree of polymerization, the bonds on carbon atoms are unsaturated and these molecules can form covalent bonds with similar molecules to form a polymer chain.

Majority of the items of daily use such as skin, clothes, paper, hair and paint are made of organic polymers. Moreover, teeth muscle, glue, cling film, starch, crab cells and marmalade are all polymeric ...