15—Cotton Fibre Tensile Strength and X-Ray Orientation

The tensile strength of single fibres and of flat bundles of fibre for 14 samples of cotton has been correlated with the orientation of the crystallites as measured by X-rays and the magnitude of the correlation coefficient found to range from 0.77 to 0.84. This is not considered to be high enough to allow accurate prediction of strength from X-ray orientation.Variation in convolution angle within a variety affects the orientation as measured by X-rays but has little influence on the strength and this observation may explain some of the lack of correlation between X-ray orientation and strength. Some data are presented to show that increasing maturity produces an increase in measured X-ray orientation without a corresponding increase in strength.When the average convolution angles of different varieties of cotton are correlated with strength, the coefficient is not significantly different from that for X-ray orientation and strength and the good correlation between X-ray angle and convolution angle suggests that the spiral of the crystallites in all cottons in the original unconvoluted form may be the same.