Intercellular Adhesive
Complex acidic polysaccharides located in the middle lamella of flax stems act as the primary glue that holds the fibre bundles to the surrounding woody core. During linen manufacture, pectin must be partially degraded through biological retting to allow the separation of textile grade fibres from the straw. If the degradation is incomplete, scutching becomes difficult and results in higher levels of broken fibre and waste.
This sugar is a major focus of mill chemistry during the pre treatment of raw flax batches.
Chemical Role
Solubility of these compounds changes significantly as the pH levels vary during the scouring and bleaching phases. High molecular weight pectin forms a firm barrier against water penetration, meaning its removal helps open the fibre structure for subsequent dyeing. Many Chinese mills use precise enzyme baths to target these bonds specifically while preserving the length of the cellulose microfibrils.
Maintaining the correct temperature ensures the enzymatic breakdown happens effectively across the entire lot.
Grading Influence
Results from retting tests evaluate the breakdown of this sticky matrix to judge the readiness of the crop for scutching. When too much residual pectin remains, the fibre feels tacky and the spinning speed must be reduced to avoid build up on the drafting rollers. Effective removal is the difference between a coarse industrial linen and a supple apparel quality fabric.
Laboratory analysis monitors this content to confirm that the finishing treatments have successfully clarified the fibre surface.
