Standard No.:	GB/T 2910.26-2017
English Name:	Textiles―Qualitative chemical analysis―Part 26:Mixtures of melamine and cotton or aramide fibers（method using hot formic acid）
Chinese Name:	纺织品 定量化学分析 第26部分：三聚氰胺纤维与棉或芳纶的混合物（热甲酸法）
Chinese Classification:	W04    Basic standards and general methods
Professional Classification:	GB    National Standard
ICS Classification:	59.080.01 59.080.01     Textiles in general 59.080.01
Issued by:	AQSIQ; SAC
Issued on:	2017-12-29
Implemented on:	2018-7-1
Status:	valid
Language:	English
File Format:	PDF
Word Count:	7500 words
Price(USD):	220.0
Delivery:	via email in 1 business day

Codeofchina.com is in charge of this English translation. In case of any doubt about the English translation, the Chinese original shall be considered authoritative. GB/T 2910 consists of the following parts under the general title Textiles - Qualitative chemical analysis: ——Part 1: General principles of testing; ——Part 2: Ternary fibre mixture; ——Part 3: Mixtures of acetate and certain other fibres (method using acetone); ——Part 4: Mixtures of certain protein and certain other fibers (method using hypochlorite); ——Part 5: Mixtures of viscose, cupro or modal and cotton fibres (method using sodium zincate); ——Part 6: Mixtures of viscose or certain types of cupro or modal or lyocell and cotton fibres (method using formic acid and zinc chloride); ——Part 7: Mixtures of polyamide and certain other fibres (method using formic acid); ——Part 8: Mixtures of acetate and triacetate fibres (method using acetone); ——Part 9: Mixtures of acetate and triacetate fibres (method using benzyl alcohol); ——Part 10: Mixtures of triacetate or polylactide and certain other fibres (method using dichloromethane); ——Part 11: Mixtures of cellulose and polyester fibres (method using sulfuric acid); ——Part 12: Mixtures of acrylic, certain modacrylic, certain chlorofibres, certain elastanes and certain other fibres (method using dimethylformamide); ——Part 13: Mixtures of certain chlorofibers and certain other fibers (method using carbon disulfide/acetone); ——Part 14: Mixtures of acetate and certain chlorofibres (method using acetic acid); ——Part 15: Mixtures of jute and certain animal fibres (method by determining nitrogen content); ——Part 16: Mixtures of polypropylene and certain other fibres (method using xylene); ——Part 17: Mixtures of chlorofibers (homopolymers of vinyl chloride) and certain other fibers (method using sulfuric acid); ——Part 18: Mixtures of silk and wool or hair (method using sulfuric acid); ——Part 19: Mixtures of cellulose fibres and asbestos (method by heating); ——Part 20: Mixtures of elastane and some other fibers (method of using dimethylacetamide); ——Part 21: Mixtures of chlorofibers, certain modacrylics, certain elastanes, acetates, triacetates and certain other fibers (method using cyclohexanone); ——Part 22: Mixtures of viscose or certain types of cupro or modal or lyocell and flax of ramie fibres (method using formic acid and zinc chloride); ——Part 23: Mixtures of polyethylene and polypropylene (method using cyclohexanone); ——Part 24: Mixtures of polyester and some other fibers (method using phenol and tetrachloroethane); ——Part 25: Mixtures of polyester and certain other fibres (method using trichloroacetic acid and chloroform); ——Part 26: Mixtures of melamine and cotton or aramide fibers (method using hot formic acid); ——Part 101: Mixtures of soybean protein composite fibre and certain other fibers. This is Part 26 of GB/T 2910. This part is developed in accordance with the rules given in GB/T 1.1-2009. This part has been redrafted and modified by adoption of ISO 1833-26:2013 Textiles - Quantitative chemical analysis - Part 26: Mixtures of melamine and cotton or aramide fibres (method using hot formic acid). Compared with ISO 1833-26:2013, this part has structural changes, with the addition of Clause 3, and the numbers of the remaining subclauses are rearranged in order. The main technical differences with respect to ISO 1833-26:2013 are as follows: ——the adjustments on technical differences are made for the normative references of this part to adapt to the technical conditions in China, which are mainly reflected in Clause 2 "Normative references”, with the following specific contents:  ISO 1833-1 is replaced by GB/T 2910.1, which is identical to the international standard; ——In Clause 3 “Terms and definitions”, the definition of melamine fiber is added. The following editorial changes have been made in this part: ——Annex A (Informative) "Qualitative identification method for melamine fiber” is added; ——Annex B (Informative) "Quantitative chemical analysis method for binary mixture of melamine fiber and polyester fiber, polyamide fiber or spandex” is added; ——The Clause “Bibliography” is added. This part was proposed by China National Textile and Apparel Council. This standard is under the jurisdiction of National Technical Committee on Textiles of Standardization Administration of China (SAC/TC 209). Textiles - Qualitative chemical analysis - Part 26: Mixtures of melamine and cotton or aramide fibers (method using hot formic acid) Warning: This part calls for the use of substances/procedures that may be injurious to the health/environment if appropriate conditions are not observed. It refers only to technical suitability and does not absolve the user from legal obligations relating to health and safety/environment at any stage. 1 Scope This part of GB/T 2910 specifies a method using hot formic acid to determine the percentage of melamine fibers after removal of non-fibrous matter, in textiles made of binary mixtures of melamine fibers with cotton or aramid fibers. This part is applicable to the mixtures of melamine and cotton or aramide fibers. Note: Annex A gives the qualitative identification method for melamine fiber; Annex B gives the quantitative chemical analysis method for binary mixture of melamine fiber and polyester fiber, polyamide fiber or spandex. 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. GB/T 2910.1 Textiles - Quantitative chemical analysis - Part 1: General principles of testing (GB/T 2910.1-2009, ISO 1833-1:2006, IDT) 3 Terms and definitions For the purpose of this document, the following term and definition apply. 3.1 melamine fiber fiber formed by cross-linked macromolecules composed of at least 85% (mass fraction) of melamine derivatives   4 Principle The melamine fiber is dissolved out from a known dry mass of the mixture with hot formic acid (90% by mass). The residue is collected, washed, dried and weighed; its mass, corrected if necessary, is expressed as a percentage of the dry mass of the mixture. The percentage of melamine fiber is obtained by difference. 5 Reagents 5.1 General Use the reagents described in GB/T 2910.1, together with those specified in 5.2 and 5.3. 5.2 90% (mass fraction) formic acid solution (density ρ=1.204g/mL at 20℃) Dilute 890mL of 98%~100% (mass fraction) formic acid (density ρ=1.220g/mL at 20℃) to 1L with water. Safety precautions: the harmful effects of this reagent shall be borne in mind, and full precautions shall be taken during use. 5.3 Ammonia, dilute solution Dilute 80mL of ammonia (density ρ=0.880g/mL at 20℃) to 1L with water. 6 Apparatus 6.1 General Use the apparatus described in GB/T 2910.1, together with those described in 6.2 and 6.3. 6.2 Conical flask with stopper The minimum capacity is not less than 200mL. 6.3 Shaking water bath or other heating equipment It is able to perform reciprocating or circular oscillation at a frequency of 160 cycles per minute, and maintain the temperature at (90±2)℃. 7 Test procedures Follow the general procedure described in GB/T 2910.1, and then proceed as follows.

Foreword i 1 Scope 2 Normative references 3 Terms and definitions 4 Principle 5 Reagents 6 Apparatus 7 Test procedures 8 Calculation and expression of results 9 Precision Annex A (Informative) Qualitative identification method for melamine fiber Annex B (Informative) Quantitative chemical analysis method for binary mixture of melamine fiber and polyester fiber, polyamide fiber or spandex Bibliography