Effects of polarizability and electronic character of phosphine ligand on the polymerization of 1,3-butadiene using Co-based catalyst

✍ Scribed by Youngchan Jang; Pilsung Kim; Ho Young Jeong; Hosull Lee

• Publisher: Elsevier Science
• Year: 2003
• Tongue: English
• Weight: 86 KB
• Volume: 206
• Category: Article
• ISSN: 1381-1169
• DOI: 10.1016/s1381-1169(03)00425-4

✦ Synopsis

The effects of phosphine ligands on the polymerization of 1,3-butadiene with Co(2-ethyl hexanoate) 2 /AlEt 2 Cl/H 2 O were investigated. Although the polarizability of phosphine ligands, i.e. the ratio of the average dipole moment to the molecular volume, had moderate impact on 1,4-cis stereoregularity, a good correlation was observed between polarizability and 1,4-cis stereoregularity regardless of the electronic character (-acceptor or -donor) of phosphine ligands. On the other hand, neither catalytic activity nor the molecular weight (M w ) of polybutadiene showed a good correlation with polarizability. Catalytic activity was affected only when phosphine ligands were inordinately strong -acceptors and -donors. High conversions of about 90% were obtained when phosphine ligands were moderate -acceptors and -donors, regardless of their steric bulk.

On the other hand, the electronic character of phosphine ligands significantly influenced the M w of polybutadiene.