BS EN ISO 1833‑17:2020 pdf – Textiles – Quantitative chemical analysis Part 17: Mixtures of cellulose fibres and certain fibres with chlorofibres and certain other fibres (method using concentrated sulfuric acid).
1 Scope This document specifies a method, using concentrated sulfuric acid, to determine the mass percentage of chlorofibres and certain other fibres, after removal of non‑fibrous material, in textiles made of mixtures of — cotton, viscose, cupro, modal, lyocell, acetate, triacetate, polyamide, polyester, elastomultiester, certain acrylic and certain modacrylic fibres with — chlorofibres (based on homopolymers of vinyl chloride), polypropylene, elastolefin, melamine and polypropylene/polyamide bicomponent. The modacrylics concerned are those which give a clear solution when immersed in concentrated sulfuric acid. This method can be used, particularly in place of the methods described in ISO 1833‑12 and ISO 1833‑13, in all cases where a preliminary test shows that the chlorofibres do not dissolve completely either in dimethylformamide or in the azeotropic mixture of carbon disulfide and acetone. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 1833‑1, Textiles — Quantitative chemical analysis — Part 1: General principles of testing 3? Terms? and? definitions No terms and definitions are listed in this document. ISO and IEC maintain terminological databases for use in standardization at the following addresses: — ISO Online browsing platform: available at https://www.iso.org/obp — IEC Electropedia: available at http://www.electropedia.org/
4 Principle The cotton, viscose, cupro, modal, lyocell, acetate, triacetate, polyamide, polyester, elastomultiester, certain acrylic or certain modacrylic fibres are dissolved out from a known dry mass of the mixture, with concentrated sulfuric acid. The residue is collected, washed, dried and weighed; its mass is The value of d is 1,00, except for melamine and polypropylene/polyamide bicomponent, for which the value of d is 1,01. 9 Precision For homogeneous mixtures of textile materials, the confidence limits of results obtained by this method are not greater than ±1 percentage point for the confidence level of 95 %.