Halide-free neodymium phosphate based catalyst for highly -1,4 selective polymerization of dienes.

Neodymium-based Ziegler-Natta type catalytic systems are known to produce polydienes with high -1,4 content. It is generally believed that in Ziegler-Natta catalytic systems, a halide or pseudohalide, whether in the catalyst itself or a separate source, is required for the success of the polymerization. In this work, we have synthesized an unusual halide-free neodymium diethyl phosphate catalyst for diene polymerization.