Dynamic elastic modulus of modified cotton fibres

Abstract

The dynamic elastic modulus of three cultivated varieties of G. hirsutum Linn, namely Samaru 26J Nigeria, Samaru 26J Glasgow and an unspecified American upland has been studied at different stages of fibre maturity using visco-elastomer. The dynamic modulus is found to be strongly dependent on both the maturity and the optical orientation angle. To eliminate the effect of convolutions on both the dynamic modulus and the helix angle, fibres are treated in liquid ammonia to get Cellulose III lattice structure and revert back to Cellulose I lattice structure using distilled water. Both the X- ray diffractograms and the scanning electron micrographs also confirm this finding. Maturity ratio is shown to have a very strong effect on the dynamic elastic modulus and not the age of the fibre. Fibres of similar maturity ratio show similar dynamic modulus, irrespective of the environmental conditions. Cellulose III and Cellulose I regenerated fibres have about the same dynamic modulus values. This shows that treatment does produce profound changes in the gross structure and calls for a fresh look at the swelling mechanism in both structures, a possible disruption of the H- bonding systems of cellulose by both treatments.