GB/T 44571-2024Test method of leatherette - Determination of free isocyanates content (English PDF)

Foreword

This document is in accordance with the provisions of GB/T 1.1-2020 "Guidelines for standardization work Part

1.Structure and drafting rules for standardization documents" Drafting is required. Please note that some of the contents of this document may involve patents. The issuing organization of this document does not assume the responsibility for identifying patents. This document was proposed by China Light Industry Federation. This document is under the jurisdiction of the National Technical Committee for Standardization of Plastic Products (SAC/TC 48). This document was drafted by: Zhejiang Hexin New Materials Co., Ltd., Jinlv Environmental Technology Co., Ltd., Jieshou Plastic Valley Renewable Resources Co., Ltd. Co., Ltd., Anhui Amway Materials Technology Co., Ltd., Kunshan Achilles New Materials Technology Co., Ltd., Zhejiang Deep Blue New Materials Technology Co., Ltd. Co., Ltd., Kunshan Xiefu New Materials Co., Ltd., Shandong Tongda Haidao New Materials Co., Ltd., Tenshou (Fujian) Microfiber Technology Co., Ltd. Co., Ltd., Hubei Qili Polymer Materials Co., Ltd., Foshan Weisda New Materials Co., Ltd., Chongqing Shuangxiang Microfiber Materials Co., Ltd., Guangdong Tianan Polymer Technology Co., Ltd., Fujian Huaxia Synthetic Leather Co., Ltd., Zhejiang Meisheng New Materials Co., Ltd., Lishui Quality Inspection Inspection Institute, Suzhou Ruigao New Materials Co., Ltd., Suzhou Best Decoration New Materials Co., Ltd., Zhejiang Luoxing Chemical Co., Ltd. Company, Nantong Deyi New Materials Co., Ltd., Zhejiang Jiake New Materials Technology Co., Ltd., Dongguan Weiside Technology Development Co., Ltd., Hefei Ketian Water-based Technology Co., Ltd. and Shanghai Huafeng Testing Technology Co., Ltd. The main drafters of this document are. Xu Yiyan, Yu Xiaojuan, Hong Bin, Huang Wanli, Xu Lili, Fan Xiaoying, Zhang Feng, Zhao Jianming, Li Xiangyu, Xu Xuri, Zhou Wenzhi, Liu Aiming, Su Hongwei, Yang Wentao, Chen Runjiao, Qian Guochun, Chen Jun, Gao Jingang, Zhu Lihong, Yao Dusheng, Chen Qiaojian, Zheng Sixian, Li Hualin, Zhang Wenfu, Zhu Youkui, Zhou Jing. Test methods for artificial leather and synthetic leather Determination of free isocyanate content Warning - Personnel using this document should have practical experience in formal laboratory work. Isocyanates are classified as hazardous chemicals, Class 6.1, toxic When handling, protective gloves, protective glasses and respiratory protection should be worn. This document does not address all possible safety issues. It is the responsibility to take necessary safety and health measures and ensure that the conditions are met in accordance with relevant national regulations.

1 Scope

GB/T 44571-2024 gives the methods for determining free isocyanate content in artificial and synthetic leather. Polyurethane synthetic leather is made by reacting isocyanates with polyols, and any monomer that has not reacted stays in the material; the diisocyanates are respiratory sensitisers, so residual free isocyanate matters both for the workers in the plant and for the user of a car seat or a shoe lining, and it is restricted in several export markets. The standard gives three methods for it: liquid chromatography, gas chromatography-mass spectrometry, and gas chromatography, each with its principle, reagents and materials, instruments and equipment and test procedure, together with the calculation of the result, the precision and the test report. It takes effect on 1 April 2025.

This document describes the liquid chromatography (LC) method, gas chromatography-mass spectrometry (GC-MS) method for the determination of free isocyanate content in artificial and synthetic leather. There are three experimental methods. GCMS method and gas chromatography (GC method). This document applies to free isocyanates (1,4phenylene isocyanate, toluene diisocyanate, Hexamethylene diisocyanate, trimethyl hexamethylene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate) content Other isocyanates (such as dicyclohexylmethane diisocyanate) are also applicable to this document.

2 Normative references

The contents of the following documents constitute the essential clauses of this document through normative references in this document. For referenced documents without a date, only the version corresponding to that date applies to this document; for referenced documents without a date, the latest version (including all amendments) applies. in this document.

GB/T 6682 Specifications and test methods for water used in analytical laboratories

GB/T 8170 Rules for rounding off values and expression and determination of limit values

GB/T 34443 Terminology of artificial leather and synthetic leather

HG/T 6064-2022 4,4'Dicyclohexylmethane diisocyanate

3 Terms and definitions

The terms and definitions defined in GB/T 34443 apply to this document.

4 Liquid chromatography (LC method)

4.1 Principle The sample was extracted with dichloromethane by ultrasonic and then derivatized with 9Nmethylaminomethylanthracene. The derivatized product was determined by liquid chromatography. Legal amount.