TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: The temperature in the extruder is 210-380 degrees C in an extruder of at least six zones. The melt mixing step (b) has a residence time of 20-2000 seconds. The melt mixing step (b) has a residence time of 25-200 indexed to a 16 mm, L/D is equal to 40 extruder. In the process, step (c) results in pelletization for further processing or melt extrusion on to fiber for further treatment. The endcap introduced during step (a) competes and denies reaction sites at the aromatic diamine for reaction by the dianhydride. The introduction of the endcap of the extruder during step (a) establishes competition for diamine reaction sites between the dianhydride and the endcap from the beginning of the extrusion process. The melt mixing step (b) has a screw speed of 100-1000 revolutions per minute. The melt mixing step (b) has a screw speed of 100-300 revolutions per minute indexed to a 16 mm, L/D is equal to 40 extruder. The endcap is a solid or a liquid, and where the process is solvent-less. The introduction of the endcap during step (a) does not cause immediate cessation of reaction of the dianhydride and the diamine which have also begun reacting during step (a). The process further comprises: (d) re-melting the imide oligomer in an extruder; (e) extruding the re-melted imide oligomer in the form of a film with or without presence of fiber such as carbon fiber, glass fiber, or synthetic carbon fiber; and (f) feeding the film into a machine for impregnation into a tape or fabric. The imide oligomer is further reacted or cured in the presence of fiber at 340-360 degrees C to form a thermosetting polyimide matrix-composite having a glass transition temperature of 300-370 degrees C. Preferred Components: The fiber can be carbon, glass, or a synthetic fiber. The fiber is carbon nanofiber which is present at 17-23 wt.%, preferably 18-22 wt.%. The imide oligomer further comprises optional additives comprising 4-phenylethynyldiphenyl methane and/or diphenylacetylene. The tape or fabric comprises carbon fibers, fiberglass and/or polymers. EXAMPLE - No suitable example given.