Radical copolymerization of N-alkylmaleimides with isobutene and the properties of the resulting alternating copolymers

✍ Scribed by Toru Doi; Akira Akimoto; Akikazu Matsumoto; Takayuki Otsu

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 513 KB
• Volume: 34
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(199602)34:3<367::aid-pola5>3.0.co;2-r

✦ Synopsis

Radical copolymerization of N-methylmaleimide (MeMI) as well as other N-alkylmaleimides (RMI) and isobutene (IB) was carried out with 2,2'-azobis(isobutyronitri1e) as an initiator a t 60°C. The initial rate of the copolymerization (R,) was dependent on the monomer composition and was maximum at the 40 mol % of MeMI in the feed. A solvent effect on the Rp and the monomer reactivity ratio was observed in this copolymerization system, i.e., copolymerization in chloroform produced a higher R, and an alternating tendency compared with those in dioxane (rMMeMI = 0.14, rIB = 0 in chloroform and rMeMI = 0.47, rIB = 0 in dioxane). The alternating copolymer of RMI and IB shows a high glass transition temperature (T,) and excellent thermal stability, e.g., the T, and the thermal decomposition temperature (Td) were 152 and 363"C, respectively, for the alternating copolymer of MeMI and IB. Both the Tg and Td increased as the concentration of the MeMI unit in the copolymers increased. Colorless transparent sheets were obtained from press molding the alternating copolymers. They showed excellent mechanical and optical properties.