X-Ray Diffraction Azimuthal Peak Deconvolution for Climate-Impacted Bast Fiber Sourcing Verification
Azimuthal XRD peak deconvolution isolates microfibril angle and crystallite alignment, exposing climate-degraded bast fibers before mill processing.
Crystallinity Index
Structural Ratio
X-ray diffraction analysis of bast fibres yields a percentage that represents the proportion of crystalline domains in the total cellulose mass. This numerical value is the crystallinity index, which determines the physical stiffness. It indicates the density of the polymer chains.
Fibre Grading
Raw flax shipments arriving at Chinese spinning mills undergo laboratory tests to determine their structural and chemical properties. The crystallinity index of each bale is recorded in the laboratory log before the material is assigned to a specific spinning run. Higher values are required for fine-count yarns, whereas lower grades are diverted to coarser yarn production for home textiles.
This test ensures that the natural variation in flax crops does not compromise the quality of the finished woven fabric.
Spinning Consequence
Spinning efficiency is closely linked to the molecular order of the raw material, as fibres with disorganized structures tend to snap under the high draft forces of wet spinning. When the crystallinity index falls below the mill’s minimum threshold, the yarn requires lower spinning speeds and higher lubrication to prevent frequent breakages. The finished yarn also exhibits uneven dye uptake because the amorphous sections absorb dye molecules more rapidly than the crystalline sections, which can cause visible banding in the woven cloth.