S. Abraham, V. Prasad, C. Pillai
Jun 1, 2002
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0
Influential Citations
6
Citations
Journal
Polymer International
Abstract
Copolyesters of 8-(3-hydroxyphenyl)octanoic acid (HPOA), a monomer with kink and flexible segment derived from cardanol, and 4-hydroxybenzoic acid (HBA) or its brominated derivative, 3-bromo-4-hydroxybenzoic acid (BrHBA), were synthesized by acidolysis melt polycondensation of the in situ generated acetoxyderivative in the presence of magnesium acetate as catalyst by a one-pot method and characterized. The formation of the copolyester was confirmed by elemental analysis, FTIR and 1H NMR spectroscopy. These polymers were highly insoluble in most solvents except highly polar solvents, such as trifluoroacetic acid. The inherent viscosities of the soluble polymers were in the range of 0.8–1.1 dlg−1. The thermal and phase behaviour of the copolyesters were studied by DSC and polarized light microscopy. Poly{(4-oxybenzoate)-co-[8-(3-oxyphenyl)octanoate]} with 50 mole% of HPOA showed a birefringent melt with opalescence and a worm-like texture of a nematic phase. The effect of bromine substitution in the analogue poly{(3-bromo-4-oxybenzoate)-co-[8-(3-oxyphenyl)octanoate]} was evident when it showed a lower transition with minimum 45% Br-HBA at 225 °C showing enhanced melt processability. These copolymers, with hydrolytically degradable aliphatic carbonyl group and better crystallinity compared to poly(hydroxyalkanoate)s, are interesting in possible biomedical applications. © 2002 Society of Chemical Industry