Commodity and Engineering Plastics

 Sometimes, commodity plastics have their properties good enough for engineering applications.

COMMODITY AND ENGINEERING PLASTICS

As shown in Fig.4.1, both the thermoplastics and thermosetting plastics, in turn, can be classified, from the usage point of view, into two groups. They are :

1. Commodity plastics, and

2. Engineering plastics.

1. Commodity Plastics

✔ The widely used plastics are called as commodity plastics.

✔ Commodity plastics generally have lower cost.

✔ Most commodity plastics are used for throwaway items such as hot/cool drink cups, plastic bags, boxes, etc.

✔ In simple terms, the plastics which are not generally used for engineering applications are known as commodity plastics. 

Examples for commodity plastics: Fig.4.14 lists some of the most commonly used commodity plastics.

2. Engineering Plastics

✔ The plastics which are used in engineering applications are known as engineering plastics.

✔ Engineering plastics have higher strength, greater environ- mental resistance, and better physical properties.

✔ Engineering plastics are more costlier than commodity plastics. 

Note Sometimes, commodity plastics have their properties good enough for engineering applications. In such cases, plastics are neither commodity plastics nor engineering plastics. That's why many consider 'cost' as the most accurate discriminating factor for these plastics. That is, lower cost plastics are termed commodity plastics and high cost plastics are engineering plastics.

Examples for engineering plastics: Fig.4.15 lists some of the `engineering plastics.