Alternating copolymerization of N-(alkyl-substituted phenyl)maleimides with isobutene and thermal properties of the resulting copolymers

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

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 522 KB
• Volume: 34
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(19960915)34:12<2499::aid-pola23>3.0.co;2-2

✦ Synopsis

Radical copolymerization of N-(alkyl-substituted pheny1)maleimides (RPhMI) with isobutene (IB) was carried out with an initiator in various solvents at 6OoC. The copolymerization of N-(2,6-diethylphenyl)maleimide (2,6-DEPhMI) with IB in benzene proceeded readily in a homogeneous system to give an alternating copolymer over a wide range of the comonomer compositions in the feed. Whereas the alternating tendency of the copolymerization of other RPhMI with IB decreased depending on the alkyl substituents of RPhMI in the following order: 2,6-DEPhMI > N-(2,6-dimethylphenyl)maleimide 2 N-(2-meth-ylpheny1)maleimide > N-(4-ethylphenyl)maleimide. The copolymerization reactivities were discussed based on the rate constants for the homo-propagations and cross-propagations. Subsequently, the effect of the solvent on the rate and the reactivity ratios was examined. It was revealed that the copolymerization in chloroform proceeded with higher alternating tendency at a higher copolymerization rate than in the copolymerizations in benzene or dioxane. The copolymers of RPhMI with IB showed excellent thermal stability, i.e., high glass transition temperature and initial decomposition temperature over 200 and 350°C, respectively.