SPS

Syndiotactic Polystyrene (SPS) was first discovered in 1985 by Dr. Walter Kaminsky and Dr. Hansjörg Sinn at the University of Hamburg, Germany. It was properly commercialised in 1997 by Idemitsu under the brand name Xarec.

Why choose SPS for your injection moulding project?

  • 1. High Heat Resistance. SPS has a melting point around 270 °C, much higher than standard polystyrene and many common engineering plastics. It maintains strength and stiffness at continuous-use temperatures up to ~200 °C, making it ideal for automotive, electronic, and industrial parts exposed to heat.
  • 2. Excellent Electrical Properties. Naturally low dielectric constant and low dielectric loss even at high frequencies. Provides outstanding electrical insulation and dimensional stability, perfect for connectors, coils, sensors, and circuit housings.
  • 3. Outstanding Chemical Resistance. SPS resists acids, bases, hydrocarbons, and most solvents, far better than conventional PS or many engineering polymers. Ideal for environments where chemical exposure or cleaning agents are present — e.g. pumps, valves, and laboratory components.
  • 4. Low Water Absorption. SPS absorbs less than 0.02 % moisture, so it maintains excellent dimensional stability and consistent electrical performance even in humid conditions. This makes it superior to nylons or polyesters that can swell or warp with moisture.
  • 5. Dimensional Stability and Precision. Its crystalline structure gives SPS minimal shrinkage and warpage during moulding. Enables tight tolerances and precise part fit, ideal for small, complex or multi-cavity moulded parts.
  • 6. Lightweight with High Rigidity. SPS combines high stiffness and low density (~1.05 g/cm³), reducing component weight without sacrificing mechanical strength. This makes it popular for automotive and electronic miniaturisation.
  • 7. Excellent Mouldability. SPS flows easily in moulds, allowing thin-wall, high-precision parts to be produced efficiently. It cools and solidifies quickly, improving cycle times and productivity.
  • 8. Weatherability and Thermal Stability. Naturally UV and heat-stable, with minimal colour change or embrittlement over time. Suitable for outdoor or high-temperature applications without the need for heavy stabiliser packages.
  • 9. Recyclable and Reprocessable. SPS can be mechanically reprocessed and reintroduced into moulding cycles with little property loss.

If you have an injection moulding project and are considering using SPS, please get in touch with our technical team on 01280 706335 for a free consultation!