Leibniz-Institut für Polymerforschung Dresden e.V.

Novel polymeric antistatic additives for plastics

SMC plates after electrostatic application of powder coating - Left: SMC without additive; Right: SMC with 3 wt.-% additive

At the plastics fair K 2013 in Duesseldorf scientists of the Leibniz-Institut für Polymerforschung Dresden e. V. (IPF) present novel concepts for antistatic treatment of thermosetting and fiber reinforced plastics (e.g. SMC).

Antistatic properties of plastics are necessary, e.g., to avoid electrostatic discharge of polymers used in electric/electronic devices or to be able to apply organic coating materials to plastic substrates by using the efficient method of electrostatic lacquer application.

The polymeric antistatic additives developed at the IPF have quite a number of advantages as compared to state-of-the art methods of antistatic treatment, which rely on application of carbon black, inorganic pigments or inorganic salts, metal powders or, recently, carbon nanotubes (CNT) and their physical mixing into the matrix.

In the novel approach, the covalent chemical coupling of the innovative additives to the polymeric network prevents migration processes and ensures the durability of the antistatic properties. The mechanical material properties and the processing behavior are not affected, as it is observed in the case of incorporation of carbon black with the required high filling degree. Another advantage of the novel additives is their transparency. Finally, they are competitive also with regard to the price, in particular when compared to nanofillers such as CNT.

Successful tests have been done with, e.g., unsaturated, polymer-based antistatic additives with ionic units which were incorporated into the matrix polymer of SMC during the molding process, forming covalent bonds. Subsequently, e.g. electrostatic powder coating of the SMC plates was possible.

The concept can be adapted also to other polymeric materials.

Contact: Dr. Michaela Gedan-Smolka