Patent attributes
Copolyetherimides compositions having high glass transition temperatures and outstanding ductility are presented. The copolyetherimides having Mw of at least 40,000 comprising isomeric bis(phthalimide) structural units within a relatively narrow range of isomer proportions exhibited Tgs of at least 240° C. and outstanding Notched Izod values. The copolyetherimides comprise oxydianiline residues and structural units of the formulas (I) and (II) (III). The copolyetherimides are characterized by a mole percentage of structural units derived from 4,4′-biphenol in a range from about 55% to about 85% of all bisphenol-derived structural units present in the copolyetherimide composition; a mole percentage of structural units derived from bisphenol A in a range from about 45% to about 15% of all bisphenol-derived structural units present in the copolyetherimide composition; and a total mole percentage of structural units derived from bisphenol A or 4,4′-biphenol of at least 95% of all bisphenol-derived structural units present in the copolyetherimide composition.
