POLYPROPYLENE (PP)

Advantages

  • Lightweight
  • Chemical resistant
  • Heat resistant

Limitations

  • Poor impact resistance at low temperature
  • Difficult to paint or bond with adhesives
  • Molded surface is not smooth with glass reinforcement

Overview

Polypropylenes offer a good balance of properties and cost unachieved by most thermoplastics.

Polypropylene offers ease of processing with excellent chemical resistance and good mechanical properties.

Glass fiber-reinforced polypropylene has improved dimensional stability, resistance to warpage, rigidity and strength. Heat deflection temperature at 264 psi is increased up to 300 °F (150 °C) for 40% glass fiber reinforced polypropylene. Polypropylene’s coefficient of thermal expansion is cut in half with 40% glass reinforcement.

Glass fiber reinforced polypropylene, when utilizing a chemical coupling agent, has significantly improved tensile and flexural strengths over regular glass reinforced polypropylene.

Polypropylene with 30% chemically-coupled glass reinforcement has a 180% improvement in tensile strength over the non-reinforced polypropylene and a 50% improvement over conventional glass-reinforced grades.

Overall, chemically-coupled polypropylene improves strength characteristics without altering the moduli, heat resistance, electrical properties, or hardness.

Talc-filled polypropylenes have improved rigidity, hardness, and heat resistance compared to the base resin.