The influence of the lateral filament texture on the compressive properties of PpPTA aramid filaments

A series of PpPTA aramid fibres with various degree of lateral orientation ranging from their usual radial-oriented lateral texture to a full random lateral texture were prepared by employing a series of different coagulating media in the fibre spinning process. The resulting variation in lateral texture did not lead to differences in linear tensile properties or crystallite dimensions. Raman spectroscopy measurements on embedded axially compressed filaments showed that the stresses for kink band initiation and propagation were independent of the degree of lateral texture. The kink band morphology and the final kink band density upon further straining were found to correlate with the shear modulus derived from combined mechanical and XRD data.