Wax Extraction
Standard testing protocols define the quantitative extraction of wax and oil residues from cellulosic fibers using organic solvent mixtures. Compliance with astm d1107 ensures that the percentage of natural waxes remaining on the fiber surface is measured accurately before finishing. This testing is applied to raw, scutching, and combed fibers to assess the baseline wax content.
Chemical Procedure
Specially configured Soxhlet extraction apparatuses boil and reflux a binary solvent mixture of toluene and ethanol through the fiber specimen for a continuous period of four hours. This action dissolves and removes the surface lipids without degrading the structural cellulose of the flax bundles, which is essential for accurate measurement. The dissolved extract is subsequently dried to a constant weight in a laboratory desiccator and measured using a precision microbalance to calculate the precise mass fraction of wax in the original sample.
This process is used to evaluate raw scutching lots and combed fibers.
Acceptance Threshold
Testing must show that the wax content is below the limit set by the buyer. If the wax content exceeds the threshold, the mill must increase the duration of the scouring stage to prevent uneven dyeing. Solvent extraction measurements are recorded in the mill log to prove compliance with trade agreements.
