The effects of growth conditions and of processing into yarn on dislocations in hemp fibres

Dislocations are irregular regions within the cell wall of natural fibres. Dislocations have also been called slip planes or nodes, and are important for the properties of natural fibres within a number of applications. This study compares the percentage of the cell wall consisting of dislocations at harvest in hemp fibres from plants grown in a green house under three different regimes (wind free, windy and dry) with the percentage found in commercial hemp yarn. As expected a higher percentage of the cell wall consisted of dislocations in the processed fibres, but the increase was only significant compared to two of the three growth regimes (wind free and windy). The dislocations were significantly larger in the yarn fibres than in the plants regardless of the growth conditions, even though both the windy and the dry conditions increased the sizes of the dislocations significantly compared to the wind-free regime. Interestingly, the typical longitudinal distances between neighbouring dislocations were found to be longer for the yarn fibres than for the fibres taken from the plants at harvest.