Mechanical properties of LaRC-IA and ULTEM melt-extruded fibers and melt-pressed films

LaRC-IA, the polyimide prepared with 3,4'-oxydianiline(3,4'-ODA) and oxydiphthalic anhydride (ODPA), is useful as a film, coating, adhesive, and composite matrix. The high temperature capability and fire resistance of polyimides also makes them attractive candidates for textile fibers for a variety of uses in the automotive, chemical, and aerospace industries. This research describes for the first time the melt-spinning of phthalic anhydride endcapped LaRC-IA and the effects of processing conditions on the mechanical properties of slightly-drawn fibers. Average draw ratios varied from 1-3.9. Tensile strengths ranged from 103-159 MPa; moduli ranged from 2.80-3.21 GPa; elongations at break ranged from 14-103%. For comparison, tensile properties of compression-molded films prepared at the same temperatures are also reported. Melt-extruded fibers and melt-pressed films of another thermoplastic, ULTEM, were also fabricated. UTEM fibers exhibited tensile strengths ranging from 138-207 MPa for average draw ratios of 4.5-10.3. Moduli ranged from 2.70-3.22 GPa. Elongations at break ranged from 47-111%.