Currently, metallocene catalyst systems based on zirconium, titanium, or hafnium have attracted the industry's attention for EPDM production. The gas-phase process developed by Union Carbide has recently been commercialized. In the study, SRI Consulting evaluated and compared these processes using either ENB or HD as the nonconjugated diene in the terpolymer, and either Ziegler-Natta or metallocene as the catalyst system for polymerization.
Polymer is recovered without steam stripping.
The gas-phase EPDM process, on the other hand, has advantages in both capital investment and production costs compared to the solution and suspension processes. However, the long retention time required for polymerization in this process makes manufacturing multiple grades less desirable than in the other processes. SRI Consulting estimates that EPDM elastomers account for about 80-85 percent of the total worldwide EP elastomer production. In addition to design and economic analysis and comparison of two pieces of emerging EPDM technology to existing conventional technology, this report includes an extensive survey of the literature with a summary of key patents. The report also identifies EPDM producers, and provides capacity and consumption for world major regions.