Polymerization behavior of electron-accepting substituted quinodimethanes

✍ Scribed by Takahito Itoh; Shouji Iwatsuki

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 972 KB
• Volume: 198
• Category: Article
• ISSN: 1022-1352
• DOI: 10.1002/macp.1997.021980701

✦ Synopsis

Abstract

This article describes the polymerization behavior of electron‐accepting substituted quinodimethanes. Chlorine‐substituted quinodimethanes (1a–c) behave differently depending on the number of chlorine substituents. Strong electron‐accepting substituted quinodimethanes like 2a–c and 4 are not homopolymerizable, but copolymerizable with donor monomers like styrene in an alternating fashion. 7,7,8,8‐Tetrakis(alkoxycarbonyl)‐quinodimethanes (3a and 3b) and 7,7,8‐tris(tert‐butoxycarbonyl)‐8‐cyanoquinodimethane (5a) show amphoteric behavior in their alternating copolymerizations and in their charge‐transfer complex formation. Some substituted quinodimethanes with two different substituents on their exocyclic carbons (5b, 6a–c, 7a–e, 8a and 8b, and 9a–e) are homopolymerizable; for instance anionic polymerization of 7,8‐bis(butoxycarbonyl)‐7,8‐dicyanoquinodimethane (6c) takes place in a living way and gives a polymer with a molecular weight above 10^6^. The homopolymerizations are equilibrium polymerization reactions and the thermodynamic parameters were determined. Their copolymerizations with styrene occur in a random fashion. The cross‐propagation step was studied by means of a linear free energy relationship and a new concept of radical alternating copolymerization is proposed.