Overview
ISO 1833-10:2019 specifies a quantitative chemical analysis method for determining the mass percentage of triacetate or polylactide (PLA) in textile mixtures using dichloromethane (DCM) as the solvent. The procedure measures the soluble component (triacetate or PLA) by dissolving it from a known dry mass, collecting and weighing the insoluble residue, and calculating the proportion by difference. The method applies to mixtures of triacetate or PLA with a wide range of fibres including wool, silk, cotton, viscose, modal, lyocell, polyamide, polyester, acrylic, polypropylene, glass fibre and several specialty fibres.
Key topics and requirements
- Scope: Determines mass percentage of triacetate or PLA after removal of non‑fibrous matter in specified fibre mixtures. Not applicable when triacetate has been partially hydrolysed (saponification) and is no longer fully soluble in DCM.
- Principle: Dissolve triacetate/PLA in dichloromethane; filter, wash, dry and weigh the residue; compute percentage by difference (general principles per ISO 1833‑1).
- Reagent: Dichloromethane (DCM) - toxic: strict safety precautions required (ventilation, PPE).
- Apparatus: Use equipment described in ISO 1833‑1 plus a glass‑stoppered conical flask (minimum 200 ml).
- Procedure essentials:
- Add 100 ml DCM per gram of specimen; stand 30 minutes with intermittent shaking (~every 10 min).
- Decant, then add 60 ml DCM, wash and filter; remove excess solvent by suction and gravity draining; rinse with hot water to remove solvent, dry and weigh.
- Use prescribed mass correction factors (d = 1.00 normally; d = 1.01 for polyester elastomultiester, elastolefin and melamine; d = 1.02 if triacetate is not completely soluble).
- Precision: Confidence limits on homogeneous mixtures are ±1 percentage point at 95% confidence.
Applications and users
- Textile testing laboratories conducting fiber composition analysis and quality control.
- Manufacturers of textile fibres and blended fabrics verifying component percentages for product labeling and specification compliance.
- Certification bodies and regulatory agencies assessing conformity with labelling and trade standards.
- Procurement, forensic analysis, and R&D groups analyzing blends containing triacetate or PLA.
Safety and practical notes
- Dichloromethane is hazardous - ensure appropriate fume extraction, PPE and waste disposal procedures.
- Method is unsuitable for triacetate that has undergone saponification and for cases where triacetate/PLA solubility is impaired.
Related standards
- ISO 1833-1 - General principles for quantitative chemical analysis of textiles.
- Other parts of the ISO 1833 series covering solvent and reagent methods for different fibre combinations.
Keywords: ISO 1833-10:2019, textiles quantitative chemical analysis, triacetate, polylactide, dichloromethane method, fiber composition testing, textile testing laboratories.