Technical Article

It is not possible every time for the designer to ask the plastic resin manufacturer to develop entirely new polymer having some typical chemical composition for a particular product application.

In most cases designers must select a material to meet their needs from one of the hundreds of material grades that are available commercially. Almost all of these commercially available plastic material grades are modified to some extent using some kind of additives. A polymeric kind of structure is used instead of simple homogeneous material.

These additives have specific roles to play, i.e some may increase stiffness while others may improve UV stability for outdoor application and others may improve flow properties. Various types of additives include Lubricants (both- external and internal), processing stabilizers, Antioxidants, plasticizers, reinforcements, flame retardants, organic and inorganic additives. These additives may also be used in combination to achieve a particular property. But the side effect of adding these additives must be seriously looked especially for critical applications. Food grade and medical application plastic material need to be checked as even small concentrations of additives may change the taste, color, or may add impurities to the basic food item / medicine. Though it may be in PPM level it may be hazardous in some areas.

The designer may use some of the additives to improve the performance including processibilty.

A simple example of new material developed using additives is a simple special colored material while a complex example would be using glass filled compounds. These additives are mixed with controlled conditions at the resin manufacturer's place.

In short a designer has wide choice of using various additives, however it should be checked for other side effects.