The mechanism of butadiene polymerization with the catalytic system NdCl 3 · 3TBP(1C 4 H 9 ) 2 AIH

The polymerization of butadiene with the catalytic system NdCl 3 · 3TBP‐(1C 4 H 9 ) 2 AlH (TBP‐tributyl phosphate) was studied. With regard to the anti‐syn ‐isomerization of both free‐ and monomer‐complexed active centers, the kinetic scheme of the propagation reaction was shown to afford adequate descriptions of the experimental dependence of the polymer microstructure on the monomer concentration. Following the results of the quantum‐chemical calculations, it was assumed that the free molecules (1C 4 H 9 ) 2 AlH coordinated competitively with the monomer molecules on the active centers in solution, which finally led to lower reactivity of the active centers. © 1993 John Wiley & Sons, Inc.