The marked tendency of thermoplastic polymers to accumulate static charges which result in adherent particles of dust and other foreign matter has required study of possible means of eliminating or reducing this property. The following have been tried: (1) Development of more electrically conductive polymers, e.g., tetracyanoquinodimethane. (2) Incorporation of additives that migrate to the surface of the plastic or fiber and modify its electrical properties. (Examples of these are fatty quaternary ammonium compounds, fatty amines, and phosphate esters.) Other types of antistatic additives are hygroscopic compounds, such as polyethylene glycols and hydrophobic slip additives, that markedly reduce the coefficient of friction of the plastic. (3) Copolymerization of an antistatic resin with the base polymer.
