Highly branched aromatic polymers polyamides

Preparation and characterization of highly branched aromatic polymers, polyphenylenes, polyesters, polyethers, and polyamides, were reviewed. These polymers were prepared from condensation of AB -type monomers, which gave noncrosslinked, highly branched polymers. The polymer properties are vastly different compared to their linear analogs due to their resistance to chain entanglement and crystallization. 

When either or both of the comonomers has a functionality higher than 2, a branched system evolves. The major limitation of the Schotten-Baumann reaction is its uses of AA and BB-type monomers, to the exclusion of AB-type monomers. This is simply due to the general unavailability of AB-type monomers in which A is an acid chloride and B is a free amine. Responding to the need, a procedure was developed over the years at duPont by which a reactive AB-type monomer is first prepared and then reacted with itself to create linear [210, 414, 415] or highly branched [416] aromatic polyamide polymers. Accordingly, an amino acid chloride hydrochloride (e.g.,)... 

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