Simulated orientational morphology from the measured transient rheology of polycarbonate-carbon fiber composites

We prepared carbon fiber (CF) reinforced polycarbonates (CFR-PC) by co-rotating twin screw extruder and injection molding. We simulated the orientational morphology of CFR-PC by inverse calculation from the measured transient stress curve using 8 mm disk rotational rheometer. The shear stress evolution was expressed by a function of the Fredholm integral of the first kind; total stress was expressed by a linear combination contributed from a stress at each orientation state. We employed an extended White-Metzner model with Dinh-Armstrong flow-fiber coupling term as a constitutive equation for the evaluation of stress at each orientation state. The probability density of each orientation state was determined by the Tikhonov regularization method from the measured stress overshoot. Finally, the orientation distribution functions (ODFs) of CFR-PC were determined by maximum entropy method from the determined probability density of orientation state. For the CFR-PCs, the simulated morphology by the ODF was well consistent with the morphology obtained by optical microscopy.

Automated summary

We prepared carbon fiber reinforced polycarbonates (CFR-PC) using co-rotating twin screw extruder and injection molding. The orientational morphology of CFR-PC was simulated by inverse calculation from the measured transient stress curve using 8 mm disk rotational rheometer. The stress evolution was expressed by a function of the Fredholm integral of the first kind, and the total stress was expressed by a linear combination contributed from a stress at each orientation state. We used an extended White-Metzner model with Dinh-Armstrong flow-fiber coupling term as a constitutive equation for evaluating the stress at each orientation state. The probability density of each orientation state was determined by the Tikhonov regularization method from the measured stress overshoot. Finally, the orientation distribution functions (ODFs) of CFR-PC were determined by maximum entropy method from the determined probability density of orientation state. The simulated morphology by the ODF was well consistent with the morphology obtained by optical microscopy for the CFR-PCs.