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Static-dissipative plastics offer special properties that help keep sensitive electronics from harm.
Manufacturers of electronic devices ideally want an electrostatic-free environment for components. Certain plastics can prevent electrostatic discharge (ESD). ESD is the transfer of charge between bodies at different electrical potentials. The main goal with ESD materials is controlling the charge during an ESD event. The best materials for the job are conductive with a high dielectric constant.
Ordinary plastics are insulators, materials that prevent the flow of electrons across their surfaces or through their volumes. This contrasts with conductors such as metal which readily support electron flow.
Special static-control plastics have electrical resistance properties between those of insulators and conductors. They dissipate static in a controlled manner through the addition of conductive fillers or fibers made from stainless steel or carbon. The efficiency with which these plastics dissipate static is significantly higher than that of insulators, but less than conductors.
Static-control plastics are designed such that they have specific properties that manage the process of charge leaking off. These properties are dielectric strength, capacitance, dielectric constant, and resistivity.
Dielectric strength is the degree to which a material will not breakdown (and become a conductor) under the application of voltage. It is commonly referred to as the strength of an insulator. Capacitance is the degree to which a material can store charge. The dielectric constant is a measure of how much electrostatic energy the material stores for a given voltage potential. Another important property for static-control plastics is resistivity.
Statically dissipative plastics have a surface resistivity...