Thermally stable, rigid dibasic acids of the formula ##STR1## wherein R.sup.1 is arylene or substituted arylene, are used to prepare thermally stable, rigid polyesters of the formula ##STR2## WHERE R.sup.2 is arylene or substituted arylene, and n is at least 10.
热稳定、刚性的二元酸的
化学式为##STR1##,其中R.sup.1是芳基或取代芳基,用于制备热稳定、刚性的聚酯的
化学式为##STR2##,其中R.sup.2是芳基或取代芳基,n至少为10。