Journal of Polymer Science Part A: Polymer Chemistry, Vol.37, No.13, 2129-2136, 1999
Synthesis and properties of novel aromatic poly(o-hydroxy amide)s and polybenzoxazoles based on the bis(ether benzoyl chloride)s from hydroquinone and its methyl-, tert-butyl-, and phenyl-substituted derivatives
Four series of poly(o-hydroxy amide)s were prepared by the low-temperature solution polycondensation of the bis(ether benzoyl chloride)s extended from hydroquinone and its methyl-, tert-butyl-, or phenyl-substituted derivatives with three bis(o-aminophenol)s. Most of the poly(o-hydroxy amide)s displayed an amorphous nature, were readily soluble in various polar solvents such as N,N-dimethylacetamide (DMAc), and could be solution-cast into flexible and tough films. These poly(o-hydroxy amide)s had glass transition temperatures (T-g) in the range of 152-185 degrees C and could be thermally cyclodehydrated into the corresponding polybenzoxazoles approximately in the region of 200-400 degrees C, as evidenced by the DSC thermograms. The thermally converted benzoxazole polymers exhibited T(g)s in the range of 215-247 degrees C and did not show significant weight loss before 500 degrees C either in nitrogen or in air.
Keywords:hydroquinone;methylhydroquinone;tert-butylhydroquinone;phenyl-hydroquinone;bis(ether benzoyl chloride)s;poly(o-hydroxy amide)s;polybenzoxazoles