Additives in plastics processing [German version]


Additive Characteristics
Antistatic agents Antistatic agents are added to plastics in order to prevent electrostatic charging of the packaging. Such charging causes plastics to attract and retain particles of dust and dirt.
Colorants Colorants, whether soluble or insoluble (pigments), inorganic or organic, are used to color plastics. Addition of colorants may sometimes have a considerable impact upon the properties (e.g. strength) of the plastic.
Flame retardants Addition of flame retardants modifies the combustion behavior of plastics, it being possible to limit not only flammability and ignitability but also the combustion process itself. Polyethylene and polypropylene, for example, intrinsically support combustion and flame retardants prevent this reaction from occurring. On the other hand, other plastics, such as PVC are self-extinguishing and stop burning by themselves.
Fillers The purpose of fillers, such as glass fiber, chalk, graphite, carbon black etc., is, on the one hand, to extend the plastics and so reduce their cost and, on the other, to improve the qualities of the plastic. Such qualities are strength, resilience and hardness.
Lubricants The purpose of lubricants is to facilitate plastics processing, for example by increasing surface slip during extrusion and so improving shaping results.
Stabilizers The task of stabilizers is to protect plastics from the effects of light, UV radiation, heat, aging. Stabilizers protect plastics from premature decomposition or impairment of their properties.
Plasticizers Addition of plasticizers modifies certain properties of a plastic: resilience is increased, while its embrittlement temperature, and likewise hardness, falls. However, the effects of plasticizers are not only positive. There are health issues associated with plasticizers and, due to their tendency to vaporize out of plastics, they are not suitable for food use.