Direct Synthesis of Thermoplastic Polyolefin Elastomers from Nickel-Catalyzed Ethylene Polymerization

As a promising alternative
to thermoset elastomers, thermoplastic
elastomers (TPEs) have attracted much attention because of their unique
properties, including processability, reusability and recyclability.
The synthesis of TPEs based on olefinic building blocks usually requires
the use of long chain α-olefins, multiple steps, and/or multiple
catalysts. The concept of using only ethylene as feedstock in a single
step is fascinating but also very challenging. In this contribution,
we report the synthesis of polyethylene-based TPEs through α-diimine
nickel-catalyzed ethylene polymerization. The stress-at-break and
strain-at-break values of these polyethylene products could be tuned
over a very wide range using different nickel catalysts and different
polymerization conditions. Most importantly, products with excellent
elastic properties could be generated in the screening process.