A uniaxially-stretched, high yield extruded film comprising a polyetherimide comprising units derived from polymerization of an aromatic dianhydride with a diamine selected from a meta-phenylene diamine, a para-phenylene diamine, and a combination thereof, wherein the polyetherimide is endcapped with an a substituted or unsubstituted aromatic primary monoamine; and wherein the high yield extruded film comprises at least 90 weight % of the polyetherimide before extrusion.