Stress Responses of Polycarbosilane Melt under an Oscillating Shear Straining

A typical oligomers material, polycarbosilane (PCS) melt, was tested by using the advanced rheumatic expansion system (ARES) with a supplemental data acquisition card and an analog-to-digital converter (ADC). The stress response of the sample at 295 °C to the oscillating shear straining deformation with a 50% shear and an angular frequency of 3.142 rad/s were collected, processed by using the fast Fourier transformation (FFT) technique, and compared to the conventional dynamic stress response of the melt provided by ARES. It was found that the stress response of the melt was no longer sinusoidal and that the main frequency and the amplitude of the stress response were consistent with those provided by the conventional testing method. The PCS at 295 °C behaved like a typical yield fluid when it under the oscillating shear straining deformation with a 50% shear and an angular frequency of 3.142 rad/s.