Overview
EN ISO 1833-9:2019 specifies a quantitative chemical analysis method for determining the mass percentage of acetate in textile mixtures using benzyl alcohol. Published by CEN/ISO, this part of the ISO 1833 series covers textiles composed of acetate mixed with certain other fibres: triacetate, polypropylene, elastolefin, melamine, polypropylene/polyamide bicomponent and polyacrylate. The method is intended to be used after removal of non‑fibrous matter and expresses the acetate content by difference.
Key topics and technical requirements
- Principle: Dissolve acetate from a known dry mass of the mixture using benzyl alcohol; collect, wash, dry and weigh the insoluble residue and calculate acetate by difference.
- Reagents: Benzyl alcohol and ethanol (in addition to general reagents in ISO 1833-1).
- Apparatus:
- Glass-stoppered conical flask (min. 200 ml)
- Mechanical shaker
- Heating apparatus/water bath to maintain (52 ± 2) °C
- Weighed filter crucible and suction apparatus
- Test procedure (high-level):
- Add 100 ml benzyl alcohol per gram of specimen.
- Shake at (52 ± 2) °C for (20 ± 1) min; repeat three extraction cycles with fresh benzyl alcohol each time.
- Filter, transfer residue, rinse with ethanol (three times), dry and weigh.
- Calculation notes:
- Follow calculation rules in ISO 1833-1.
- Density correction factor d = 1.00 (except melamine where d = 1.01).
- Precision: Confidence limits on homogeneous mixtures are ≤ ±1 percentage point at the 95% confidence level.
- Standards status: This edition (2019) supersedes earlier versions (e.g., EN ISO 1833-9:2010; ISO 1833-9:2006).
Applications and users
This standardized benzyl alcohol extraction method is useful for:
- Textile testing and quality control laboratories verifying fibre composition percentages.
- Manufacturers validating raw material and blended-fibre product specifications.
- Import/export inspectors and conformity assessment bodies assessing labelling and regulatory compliance.
- Research and development teams working on fibre blends and product performance characterization.
Keywords: EN ISO 1833-9:2019, benzyl alcohol method, acetate content, quantitative chemical analysis, textiles, acetate/triacetate, fibre composition testing.
Related standards
- ISO 1833-1 - Textiles - Quantitative chemical analysis - Part 1: General principles of testing (normative reference for procedures, calculations and general apparatus).
- Other parts of the ISO 1833 series cover different solvent or reagent methods for other fibre mixtures. Consult the ISO catalogue for the full series.