Influence of external N-containing donors on the neodymium-based catalytic system for 1,3-butadiene polymerization

• Key Words:CHAIN TRANSFER POLYMERIZATION; BUTADIENE POLYMERIZATION; LANTHANIDE CATALYSTS; ISOPRENE; COPOLYMERIZATION; COMPLEXES; SESQUICHLORIDE; DIENES
• Abstract:Evaluation of the heteroatom tolerance capability of neodymium-based precatalysts and its accompanied catalytic influences is of great significance for industrial production of polybutadienes because the corresponding active species is highly sensitive to heteroatom-based impurities that are usually inevitable in the polymerization system. Based this consideration, the present research disclosed a systematical study of the influence of N-containing donors on a ternary Nd-based system of Nd(vers)(3)/DIBAH/TEA/EASC. It was found that the presence of 1% of such donors, regardless of their types that bears different electronic/steric properties, brought little influence on the catalytic activities as well as the cis-1,4-stereoselectivities of the catalytic system, giving cis-1,4-enriched polybutadienes with comparable yields. Furthermore, the presence of such a concentration of N-donor also brought little influence on the coordinative chain transfer polymerization behaviors of the system, giving narrowly distributed polybutadiene products in a well-controlled manner. Nevertheless, further increasing the concentration of N-donors to >1% eventually led to a gradually decreased polymer yields due to the poison of the corresponding active species, and the obtained catalytic efficiencies were highly dependent on the types of N-donors. The influence of the N-donor on other parameters of the products, that is, molecular weights, polydispersities, and so forth, were also investigated, and the specific reasons were proposed.
• Volume:139
• Issue:34
• Translation or Not:no