This Nordtest method specifies an analytical procedure for determining the amounts of natural fibres and synthetic fibres which are present in sewn or needle-punched composite mats.
The method is suitable for determination of all natural fibe tyes including flax, hemp, jute, sisal, viscose, and kenaf. The method also allows determination of syntehtic fibre content in the materials when the polymers involved are polyethylene (PE), polypropylene (PP), or other types which cannot be degraded by the chemicals involved (concentrated sulphuric acid and hydrogen peroxide).
It should be noted, however, that some components of commercial polymers might be attacked and dissolved by the procedure used in this method. In such cases a small correction to the apparent results may be required.