Tamara Wilhite is a technical writer, industrial engineer, mother of two, and published sci-fi and horror author.
Plastics naturally resist the flow of electricity and dissipate a static charge. The electrical properties of polymers depend on the additives in the material as well as the humidity and the temperature of the surrounding environment. Several organizations have issued standards for determining the electrical properties of plastics, measuring the properties of conductive plastics and the performance of plastic insulation for electrical wiring.
Formal standards have been created for electrically conductive plastics and plastics used to insulate electrical conductors by groups as diverse as the IEC and ASTM International.
ASTM Standards for the Electrical Properties of Plastic
The conductivity of plastics is naturally low; they are used as insulating materials due to their inability to carry electricity. ASTM D149 is the American standard for determining the dielectric strength of plastic.
The dielectric constant or permittivity of plastics is found per ASTM standard D150.
ASTM D257 is the standard test procedure for measuring how well a material resists a moving charge.
ASTM D2132 is the test procedure for determining the resistance of electrical insulating material to erosion by dust. ASTM D790-10 is the test procedure for determining the flexure properties of plastic used to insulate electrical wire, measuring how well it withstands bending.
ASTM D672-10 is a similar flexure test but using four point bending of the sample. The thickness of the insulation material can be found using ASTM D374.
ASTM D1711 gives the standard terminology used for plastics as electrical insulation ASTM D176-07 gives the standard methods for testing the compounds used in electrical insulation. ASTM D176-07 includes test methods for the dielectric strength and dielectric constant of additives that are added to polymers.
The process for testing the tensile properties of laminated materials is typically performed per ASTM D638-10. However, ASTM D229-09B is the process used for electrical insulation.
ANSI C33.60 is the standard for underground circuits with plastic insulation. ANSI C33.80 is the ANSI standard for wires insulated with plastic protective coverings. This standard is cross-referenced with Universal Laboratories standard UL 83.
ANSI C59.87 was the standard for acetate sheet and film. This standard along with ASTM D1202-84 was withdrawn in 1990. ANSI C59.11 is the ANSI approved process of testing the impact resistance of electrically insulated wires.
IEC Standards for Conductive Polymers and Electrical Insulators
Electrically conductive plastics are often used as electronic components. The Independent Electrical Contractors or IEC has issued standards for electronic components made from conducting polymers as well as electrical insulation.
IEC 60384-13 is the standard for capacitors made from electrically conducting polypropylene film. IEC 60384-24 is the standard for capacitors made with electrically conductive polymer electrolyte.
IEC 243-1 is the test procedure for determining the electrical strength of plastic insulating tubes. New standards for conducting polymers will be issued as they are integrated into currently theoretical applications like flexible solar cells.
ISO Standards for Plastics
Electrically conductive plastics are used in flexible electronics, thin assemblies and transparent displays. ISO standard 472 gives the vocabulary for other ISO standards for plastic. There are no polymers that conduct an electrical charge without the addition of conductive additives, though plastics differ in how well they conduct or resist an electrical charge.
ISO 9944 outlines the process for determining the electrical conductivity of plastic made from phenolic resins. ISO 8031 outlines the process of determining the electrical resistance of rubber hosts and tubing.
ISO 16525 is a set of nine standards for testing conductive adhesives. ISO 16525 part 2 or ISO 16525-2 gives the test method for determining the electrical characteristics of electrically conductive adhesives.
ISO 60893-2 is the specification for laminated sheets used as electrical insulation.
Universal Laboratories standard 83 is for thermoplastic insulated wires and cables. Universal Laboratories publication UL 746A gives the UL's recommended procedures for determining the electrical and mechanical properties of polymers. UL tests can be performed on ASTM standard plastic test bars.