Dendritic aromatic polyamides and polyimides

The syntheses and properties of dendritic and hyper-branched aromatic polyamides and polyimides are reviewed. In addition to conventional stepwise reactions for dendrimer synthesis, an orthogonal/double- stage convergent approach and dendrimer syntheses with unprotected building blocks are described as new synthetic strategies for dendritic polyamides. Hyperbranched polyamides and polyimides composed of various repeating units are presented. Besides the self-polycondensation of AB(2)-type monomers, new polymerization systems with AB(4), AB(8), A(2) + B-3, and A(2) + BB'(2), monomers have been developed for hyperbranched polyamides and polyimides. The copolymerization of AB(2) and AB monomers is discussed separately with respect to the effects of branching units on the properties. (C) 2004 Wiley Perioclicals, Inc.