Synthesis of a high-trans 1,4-butadiene/isoprene copolymers with supported titanium catalysts

✍ Scribed by Aihua He; Baochen Huang; Shuke Jiao; Youliang Hu

• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 115 KB
• Volume: 89
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/app.12216

✦ Synopsis

Abstract

The copolymerization of butadiene (Bd) and isoprene (Ip) with a supported titanium‐triisobutyl aluminum catalyst system was studied. An analysis using differential scanning calorimetry, X‐ray diffraction, and ^13^C‐NMR spectra indicated that products with 25–60 mol % Bd units were random copolymers and that the melting temperatures and glass‐transition temperatures (Tg) were 30–40 and −74°C (or thereabout), respectively, which were very similar to those of natural rubber. The chemical structure of these copolymers was characterized by a high‐trans 1,4‐configuration: the trans 1,4‐content of Ip units was greater than 98%, and the trans 1,4‐content of Bd units was greater than 90%. The reactivity ratio of Bd was greater than that of Ip (r~Bd~ = 5.7 and r~Ip~ = 0.17). The sequence distribution of the monomer units of the copolymers followed a first‐order Markov statistical model. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1800–1807, 2003