Abstract

The polymerization of 1,3‐butadiene (BD) by the ternary Ziegler/Natta (Z/N) catalyst system neodymium versatate (NdV)/ethylaluminum sesquichloride (EASC)/aluminum alkyl is investigated. Special attention is paid to the impact of the aluminum alkyl on the polymerization kinetics and on the control of molar masses. In this respect diisobutyl aluminumhydride (DIBAH) and triisobutylaluminum (TIBA) are compared. Within a broad range of n Al‐Alkyl/n NdV‐ratios for both aluminum compounds the features of a living polymerization with a reversible exchange of the living polybutadienyl chains between neodymium (Nd) and aluminum are observed. The equilibrium position of this reaction is different for TIBA and DIBAH. At the same molar loadings DIBAH results in polybutadienes with molar masses which are 1/8 of those obtained in the presence of the cocatalyst TIBA. This difference is explained by a significantly more facile substitution of a hydride moiety from DIBAH than an isobutyl group from either DIBAH or TIBA by a living polybutadienyl chain.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.