Synthesis and characterization of new adamantane-eased cardo polyamides

A novel series of cardo polyamides bearing the 2,2-adamantylidene unit were directly prepared from a new adamantane-based dietheramine, 2,2-bis[4-(4-a minophenoxy)phenyl]adamantane, with various aromatic dicarboxylic acids usi ng triphenyl phosphite (TPP) and pyridine as condensing agents. These polya mides had inherent viscosities ranging from 0.44 to 0.89 dL/g. All the poly mers showed an amorphous nature by X-ray diffraction measurements, and most of them were easily soluble in polar aprotic solvents such as NMP and DMAc . The flexible and tough films cast from the polymer solutions possessed a tensile strength of 91-101 MPa and an elongation-at-break of 5-13%. The pol yamides were thermally stable up to 450 degrees C in air or in nitrogen. Mo st of them revealed distinct glass transition on the differential scanning calorimetry (DSC) traces, and their T(g)s were recorded in the range of 230 -269 degrees C. Softening temperatures (T-s) of these polyamides were in th e range of 272-308 degrees C by thermomechanical analysis (TMA). (C) 1999 J ohn Wiley & Sons, Inc.