TOPAS cyclic olefin copolymer has electrical properties, such as low dielectric constant (low permittivity), that are matched only by fluoropolymers and low temperature plastics. This makes TOPAS COC an attractive material for electronic components such as antennas, and in other high frequency or low permittivity applications. COC can be used alone, or blended with olefin plastics like polyethylene and polypropylene to raise heat resistance of these cost-effective resins in such applications.
What Is TOPAS COC?
COC is an acronym for Cyclic Olefin Copolymer. These high-performance thermoplastic, amorphous polymers are created via the combination of a cyclic olefin monomer known as norbornene, with the common plastic building block ethylene. In their natural state, COC plastics are rigid and glass-clear. At TOPAS Advanced Polymers, we manufacture a broad lineup of COC grades with heat resistance ranging from room temperature to 170C (338F). In addition to electronic products, TOPAS COC is widely used for its unique performance benefits in food, medical, and general-purpose packaging, medical devices and containers, diagnostic devices and disposables, and optical componentry including modern touchscreen layers.
TOPAS COC enables miniaturization of components. With amazing detail reproduction at even submicron scale, high flow for complex geometries, and high dimensional stability, it's become the clear choice for the compact, lightweight products of tomorrow.
Electronics environments can be challenging to ordinary plastics. Beyond heat resistance, chemical exposure is a potential threat. TOPAS COC is resistant and serves as a barrier to chemicals as varied as alcohols, DMSO, acetone, acids, bases, and more. These and other polar materials can wreak havoc with many common plastics. This makes TOPAS COC the best solution for many applications where chemical exposure is a risk. TOPAS resins are also moisture resistant and provide exceptional moisture barrier.
TOPAS COC is an incredibly pure polymer. Leachables and extractables are extremely low, as evidenced by its common use in high purity medical applications where medical glass and other plastics fail. Because offgassing can be an issue in electronics manufacturing, why not start with as pure a material as possible?
Dielectric Constant Values for Several Polymers:
- Cyclic olefin copolymer (TOPAS® COC), 2.2
- Polytetrafluoroethylene (PTFE), 2.1
- Polypropylene (PP), 2.2
- Polyethylene (PE), 2.2
- Polystyrene (PS), 2.5
- Polyethylene terephthalate (PET), 3.0
- Polyvinyl chloride, PVC, 3.2
Consistent Properties for Reliable Performance
Many polymers are sensitive to moisture, meaning that when humidity changes, films and components may suffer subtle shifts in dimensional and electronic properties. TOPAS cycloolefin polymer is unaffected by moisture, and because most grades are 100% amorphous, dimensional accuracy is not affected by crystallization as many plastics can be. Blends of semicrystalline resins (PP, PE) with COC are more dimensionally stable in processing. When precise and consistent performance is essential, TOPAS COC is the safe choice for tight tolerances and stable electronic properties.
TOPAS cycloolefin polymers can be processed by most common thermoplastic resin techniques. Injection molding, and cast and blown film extrusion are all widely utilized. Solvent casting is also possible. Flexible or soft items can be made from TOPAS Elastomer E-140, an elastomeric grade of COC with high purity that can be injection molded, overmolded or extruded into films.