Spread the love

A new, highly configurable polycyclopentene rubber compound offers high impact resilience, excellent cold resistance, low compression set, especially at low temperature, and absorbs vibration. Originally developed for vehicle tires, the compound offers both a high level of wet-grip and low rolling resistance.


Anticipated applications include sports equipment such as shoes, golf balls, club grips and racquet handles; seals, mounts, and vibration-dampers; and other applications where impact, cold temperature performance, or vibration absorption is important.

Zeon developed the rubber polymer, called polycyclopentene rubber (CPR), using ring-opening metathesis polymerization (ROMP). ROMP opens the ring and produces a branchless polymer chain. Chain transfer agents can introduce a wide variety of termination modifiers during polymerization that dramatically alter the physical properties of the rubber, its bonding characteristics, and other properties such as impact resilience (with terminal alkoxy groups, amino groups, and others). ROMP provides many advantages in producing this unique rubber. For example, with conventional rubber, it is difficult to introduce modified groups to the molecular branches. However, for CPR, introducing a modified group is greatly simplified. Consequently, the modification rate of this rubber is much higher than that of conventional rubber.

Zeon has obtained several patents in Japan and has filed world-wide patents.

Benefits Summary

  • CPR is a straight, non-branching molecule synthesized using ROMP. Branching affects the ability of the molecules to move relative to one another, whereas polymers without branches such as CPR decrease the glass transition temperature, leading to excellent performance in cold temperatures.
  • Its branchless molecule makes CPR easily modified, and allows the molecule to be modified on both ends. o Materials blend and disperse more evenly in polycyclopentene than in other rubber compounds.
  • The material is highly elastic, with low viscosity.
  • CPR offers good compression set, even when cold.
  • The material is suitable for anti-vibration and sealing applications. more

Development Summary

Zeon is now able to provide small evaluation samples to potential customers and development partners. more

IP Summary

Patent information has not been disclosed.

Spread the love