Production,structure, and mechanical properties of carbon plastics based on a crystallizing polyimide matrix modified by carbon nanofibers

Carbon-fiber composites have been made under laboratory conditions on the basis of partially crystallized polyimide (PI) matrices of R-ODFO type as modified by carbon nanofibers of VGCF type. The R-ODFO matrix is modified by nanofibers in an amount of 3 mass %, which leads to the following: firstly, an approximately tenfold reduction in the time for the crystallization of the PI matrix, and secondly, the viscosity of interlayer failure in the carbon plastic (for fibers Elur-0.08P) on the basis of the R-ODFO/VGCF composite is maintained at the fairly high level of about 1100 J/m² even with a high degree of crystallinity (about 40%) in the PI matrix, which cannot be done for the unmodified R-ODFO matrix. Triple composite can be made from a PI matrix, carbon microfibers of Elur type (volume content about 55%) and VGCF nanofibers (weight content in PI matrix about 3%), which provides a heat-resisting carbon plastic with a fairly high viscosity for interlayer failure. Translated from Khimicheskie Volokna, No. 4, pp. 80–84, July–August, 2008.