Butadiene polymerisation using binary neodymium-based catalyst systems. The effect of catalyst preparation

Abstract The influence of preparation conditions on the activity of NdCl 3 .3TBP-TIBA catalysts for the polmerisation of butadiene have been investigated. The highest catalysts activities and resulting polymer molecular masses have been found where the catalyst is “preformed” in the presence of precise and small amounts of butadiene (molar ratio [Butadiene] [Nd] = 2 ) and is aged for 1 hr at 20 °C. Polybutadienes with a 1,4- cis content of 98–99% are readily achieved irrespective of the method of catalyst preparation. The enhanced reactivity of the “preformed” catalyst is explained in terms of a stable π-allylic complex involving the butadiene unit.