The Spiral Angle of Cotton

Abstract

Spiral angles of segments (interconvolution tracts) of single cotton fibers have been obtained by taking the largest apparent spiral angle on two x-ray microcamera photographs made of the center of the segment, or on several microcamera photographs taken along the length of the segment. The mean of the spiral angle obtained for several segments in this manner is found to be in good agreement with the mean of the value obtained for these same segments by the Hartshorne optical method. Measurements of the spiral angle on six varieties of cotton representing a broad range of x-ray angles (50% angles), using this optical method, show that the spiral angle is a constant in the range of 20-23°.

Keywords

Textile materials. Non-ellipticity non-perpendicularity. Retardation (optical)extinction polarization rotation (analyzer)x-rays x-ray diffraction photomicrographs fine structure (fibers). Helix twist crystalline orientation. Cotton Microradiography light microscopy optical instruments x-ray apparatus polarizing microscope cameras photography mathematical analysis equations.

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References

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