Anionic polymerization of fluorostyrenes

✍ Scribed by K. Sugiyama; T. Ishizone; A. Hirao; S. Nakahama

• Publisher: John Wiley and Sons
• Year: 1995
• Tongue: English
• Weight: 788 KB
• Volume: 46
• Category: Article
• ISSN: 0323-7648
• DOI: 10.1002/actp.1995.010460604

✦ Synopsis

Anionic polymerizations of 2-, 3-, and 4-fluorostyrenes (2-, 3-, and 4-FSt) were carried out at -78 "C in THF with sec-butyllithium, oligo(a-methylstyryl)lithium, -dipotassium, and (l,l-diphenyl-3-methyl-pentyl)lithium as initiators to give the respective polymers in quantitative yields. The propagating carbanion derived from 2-FSt is found to survive at least for 5 min at -78 "C, affording the anionic living poly(2-FSt) with predictable molecularweight and very narrow molecular weight distribution. The addition of styrene to the anionic living poly(2-FSt) in THF affords poly(2-FSt)-b/ock-polystyrene in quantitative efficiency, indicating the high nucleophilicity of the propagating carbanion of 2-FSt. During the polymerization of 3-FSt, the benzyne intermediate is formed probably due to meta-fluoro substitution to cause polymer coupling reaction. Poly(4-FSt) produced has narrow molecular weight distribution and slightly higher molecular weight than the calculated one. The results of the polymerizations of 2-FSt and 4-FSt suggest that persistency of the propagating carbanionic species of 4-FSt is slightly lower than that of 2-FSt at -78 "C.