Direct condensation polymerization of N-alkylated aminobenzoic acid was carried out using hexachloroethane, triphenylphosphine and pyridine as condensation reagents. Pale-yellow, fibrous polymers (PABAn, where n is the number of carbon atoms of the side chain) were obtained in 46–87% yields with an inherent viscosity of 0.30–1.18 per 100ml g−1 (sulfuric acid, 30 °C). DSC analysis and powder X-ray scattering of polymer samples indicated that PABAn with Me, Pr, Bu, Pe and Ste as side chains were crystalline polymers. X-ray scattering profiles indicated that PABAn with n=0, 3, 4 and 5 crystallized in an orthorhombic lattice, whereas PABA1 crystallized in a monoclinic lattice. PABA17 crystallized with hexagonal packing at the long side chain with an interplanar spacing of 4.2Å.
- Yuji Shibasaki
- Yoko Abe
- Yoshiyuki Oishi
