The New Measurement Method of Blending Ratio of PTT/PET Fiber Blends by Centrifugal Separation

Abstract

Abstract:The PTT fiber is one of the elastic polyester fibers Owing to the similar physical and chemical properties of PTT fiber and PET fiber, the current testing standard methods are difficult to measure their blending ratios. According to the density of PTT (1.33 g/cm 3 ) is slightly lower than PET (1.38 g/cm 3 ), so the density difference of these two fibers has been used to develop a new quantitative measurement method here. In this work, a mixture liquid with certain densities were made by mixing with different ratio of xylene and carbon tetrachloride, then the samples of PET/PTT blending fiber were put into the liquid. Finally, the two kinds of fibers were well separated by using the centrifugal force, and their blending ratios were accurately determined. Optimal centrifugal separation process was obtained: the blending fiber was cut into powder, centrifugal speed was set at 800 r/min; centrifugal time was 5 minutes; solid-liquid ratio was 0.04:35 (g/mL). This simple separation method could be used to determine the blending ratios of other special fibers, and the automatic measurement technology would be promoted forward.