Deformation Characteristics of Plastics

Polymeric materials display different characteristics when heated. These characteristics depend on various factors, including the chemical structure of the polymer molecules and the type of intermoleeular bonding forces. 

Injection molding is a primary processing method. In other words, the material must exist in a plastic state so that it can be processed. This plastic state is characterized by the viscous flow properties exhibited by raw plastic materials such as powders or granulates. 

The characteristics displayed by polymeric materials when subjected to heat- 

The polymer is a hard material at room temperature. Because the individual macromolecules barely move, they are held together by intermolecular forces. An increase in temperature causes the macromolecules to move with greater intensity. The intermolecular bonds loosen and the strength of the material decreases, while its extensibility and ductility increase. 

Tg = glass transition temperature Tf = flow temperature range Td = decomposition temperature 

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