Quantitative Fiber Mixture Analysis by Scanning Electron Microscopy

Abstract

Part I of this series described the analysis of blends of the specialty fibers mohair and cashmere with sheep's wool by scanning electron microscopy (SEM), assuming equal densities and circular cross sections for the components. A bias may be expected in the analysis of other noncircular and medullated specialty fibers through systematic errors in determining the fiber diameters and densities. To determine whether the SEM method is subject to such a bias, blends were prepared of wool with angora rabbit hair, which can be regarded as an extreme example of noncircularity and med ullation. The results show that the blends can satisfactorily be analyzed by introducing a specific density for angora rabbit hair of 1.15 g/cm 3. No systematic bias of the results due to cross-sectional irregularities or to a density distribution of the rabbit hair could be detected. For the angora/wool blends, the errors of analysis compare favorably with those of cashmere/wool and mohair/wool blends.