Evaluating the oil content of cellulose acetate fibers with the dielectric spectrum

The dielectric spectrums of the cellulose acetate fiber/air (C/A) samples and the cellulose acetate fiber/air/oil (C/A/O) samples were measured with a broad band dielectric spectrum measurement system at frequencies with a logarithmic distribution from 0.1 Hz to 20 MHz. The experimental results showed that for the C/A samples, the relative permittivity varied weakly with frequency for the C/A samples, especially in the high frequency band. Hence, the mass of the cellulose acetate fibers was estimated by the dielectric spectrums of the C/A samples at a high frequency. For the C/A/O samples, the relative permittivity increased rapidly while the frequency decreased in the low frequency band, but it had little interaction with the frequency at the high frequency band. Therefore, the oil mass was estimated by dielectric spectrums of the C/A and C/A/O samples using the low frequency band. The oil content of cellulose acetate fibers was then calculated along with the estimated oil mass and cellulose acetate fibers mass.