Q&A Safety

Why are there some additives in plastics?

Plastics are made from base polymers to which blends of substances, known collectively as additives, are incorporated.

Additives change the characteristics of a plastic material causing it to gain new properties in the same way as adding butter to caramel changes its consistency: caramel is hard when it is only made with sugar but becomes soft when some butter is added.

Additives provide a large range of useful performances to plastics:

  • Plasticizers give flexibility,
  • Anti-oxidants help maintain mechanical properties under heat and oxygen aging,
  • UV blockers protect consumer eyes and skin from sun radiation,
  • Pigments give colours (or translucency),
  • Flame retardants improve  the resistance of materials to fire,
  • etc.

The principle of using additives to improve materials is not specific to plastics. For example, additives transform iron into steel and glass into crystal:

  • Iron is a ductile, soft metal. Adding 3% carbon transforms iron in steel and makes it tensile resistant.
  • Crystal is 70% glass and 30% lead. Adding lead to glass makes it harder and more translucent.

In addition to bringing extra properties to polymers, additives can also be used to make the most of the manufacturing processes of plastic products:

  • Lower production temperatures: lower energy expenditure,
  • Optimized material consumption: better resource efficiency,
  • Improved flow properties (melting, moulding, drying, etc.) : lower costs,
  • Reduced cleaning effort…

Additives, by making products last longer, also contribute to the reduction of raw materials consumption. In fact, our world today would be a lot less safe, a lot more expensive and a great deal duller without the additives that turn basic polymers into useful plastics.

Like constituents can migrate from all materials (paper, inox, glass…), additives can migrate from plastics, but in very limited amounts. In order to ensure consumer safety in more sensitive applications (food contact, medical devices, toys…), the migration potential of additives out of plastics is evaluated and controlled by authorities.


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