Elucidating the formation of structural defects in flax fibres through synchrotron X-ray phase-contrast microtomography

The creation and ultrastructure of kink-bands in flax fibres are key issues for developing more performing biobased composite materials. Nevertheless, despite many hypotheses structural characterisation, the exact origin moment they appear remain unexplained. Here, by using cutting-edge techniques such as microtomography, a range stems fibres, from green stem to stretched were morphologically explored. study shows that all extracted whether scutched, combed or stretched, contain significant amounts kink-bands, which can be identified large pores contain. On other hand, at scale retted stems, tomographic analysis does not reveal any kink-bands. These original observations suggest stress undergone plants during their growth is sufficient, without major lodging accidents, generate these defects; latter only revealed after mechanical extraction fibres. Hypotheses regarding kink-band appearance deformation levels also given complete observations.