| abstract |
There is disclosed a method for the preparation of very high cis-1,4-polypentadiene which comprises polymerizing cis-1,3-pentadiene, also known as cis-piperylene, with a ternary catalyst system comprising (A) a soluble chromium compound such as chromium salts of organic acids, organic complex compounds of chromium containing tridentate organic ligands, and pi -bonded organochromium compounds, (B) an organometallic, such as trialkylaluminums, dialkylmagnesiums or dialkylzincs, and (C) dialkyl hydrogen phosphites. |