GB/T 17821-2025 English PDFUS$219.00 · In stock
Delivery: <= 3 days. True-PDF full-copy in English will be manually translated and delivered via email. GB/T 17821-2025: Rubber latex - Determination of density between 5 ℃ and 40 ℃ Status: Valid GB/T 17821: Historical versions
Basic dataStandard ID: GB/T 17821-2025 (GB/T17821-2025)Description (Translated English): Rubber latex - Determination of density between 5 �� and 40 �� Sector / Industry: National Standard (Recommended) Classification of Chinese Standard: B72 Classification of International Standard: 83.040.10 Word Count Estimation: 10,141 Date of Issue: 2025-04-25 Date of Implementation: 2025-11-01 Older Standard (superseded by this standard): GB/T 17821-2008 Issuing agency(ies): State Administration for Market Regulation, China National Standardization Administration GB/T 17821-2025: Rubber latex - Determination of density between 5℃ and 40℃---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.ICS 83.040.10 CCSB72 National Standard of the People's Republic of China Replace GB/T 17821-2008 Determination of density of latex at 5℃ to 40℃ (ISO 705.2015, MOD) Released on 2025-04-25 2025-11-01 Implementation State Administration for Market Regulation The National Standardization Administration issued Table of contentsPreface III Introduction IV 1 Scope 1 2 Normative references 1 3 Terms and Definitions 1 4 Principle 1 5 Instruments 1 6 Sampling 2 7 Test Step 2 8 Results show 3 9 Test Report 4 References 5ForewordThis 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. This document replaces GB/T 17821-2008 "Determination of density of latex at 5℃ to 40℃". Compared with GB/T 17821-2008, In addition to structural adjustments and editorial changes, the main technical changes are as follows. a) The scope has been changed (see Chapter 1, Chapter 1 of the.2008 edition); b) the term “concentrated natural rubber latex” has been deleted (see 3.2 of the.2008 edition); c) Added a chapter on “Principles” (see Chapter 4); d) The sampling procedure has been changed (see Chapter 6, Chapter 5 of the.2008 edition); e) Added provisions on temperature correction (see 7.2); f) Added the recommendation on determination at standard temperature (see 7.4). This document is modified to adopt ISO 705.2015 "Determination of density of latex at 5℃ to 40℃". This document has the following structural adjustments compared to ISO 705.2015. --- Added the introduction and placed the content of ISO 705.2015 Chapter 1 that belongs to the purpose statement. The technical differences between this document and ISO 705.2015 and their reasons are as follows. --- Changed the scope (see Chapter 1, Chapter 1 of ISO 705.2015) to adapt to the provisions of GB/T 1.1-2020; --- The term "concentrated natural rubber latex" (see 3.2 of ISO 705.2015) has been deleted to adapt to the modification of the scope; --- Changed the principle (see Chapter 4, Chapter 4 of ISO 705.2015) to provide a reasonable explanation of the principle; --- ISO 123 (see Chapter 6) has been replaced by the normative reference GB/T 8290 to adapt to the provisions of my country on latex sampling; --- Added provisions on temperature correction (see 7.2) to adapt to my country's technical conditions and increase operability; --- Change "should be as close as possible to the temperature of latex" to "preferably as close as possible to the temperature of latex" (see 7.3, ISO 705.2015 7.3), to avoid contradictions; --- Added recommendations on determining the density of latex samples at standard temperature (see 7.4) to better meet the test requirements. 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 the China Petroleum and Chemical Industry Federation. This document is under the jurisdiction of the National Technical Committee on Rubber and Rubber Products (SAC/TC35). This document was drafted by. Agricultural Product Processing Research Institute of Chinese Academy of Tropical Agricultural Sciences, Yunnan Natural Rubber and Coffee Product Quality Supervision and Inspection Testing Station, Chinese Academy of Tropical Agricultural Sciences. The main drafters of this document are. Luo Zirong, Tao Jinlong, Xu Yongyuan, Li Yimin, Pu Ju, Li Jihua, Li Fengwei, Li Bowei, Zhang Beilong, Lu Guang, Li Tao. This document was first issued in.1999, revised for the first time in.2008, and this is the second revision.IntroductionThis document is intended for use in calculating the density of a measured volume of glue where direct weighing or controlled laboratory temperature is not possible. Formulated for the quality of milk. Determination of density of latex at 5℃ to 40℃ Warning. People who use this document need to have practical experience in formal laboratory work. This document does not address all possible safety issues. The user is responsible for taking appropriate safety and health measures and ensuring that the conditions stipulated by relevant national laws and regulations are met.1 ScopeThis document describes the principle of determining the density of latex at a temperature of 5°C to 40°C and specifies the measuring instrument, sampling, test procedures, Expression of results and contents of test report. This document is applicable to various natural rubber latexes as well as synthetic latexes, compounded latexes and pre-vulcanized latexes, and also to rubber aqueous dispersions. The temperature corrections listed in 8.2 of this document may not always apply to the above latexes.2 Normative referencesThe contents of the following documents constitute 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 to This document. GB/T 8290 Latex Sampling (GB/T 8290-2021, ISO 123.2001, MOD)3 Terms and definitionsThe following terms and definitions apply to this document. 3.1 density The mass divided by the volume at a specified temperature. Note. Density is expressed in megagrams per cubic meter (Mg/m3).4 PrincipleFill a density bottle with latex sample and calculate the density of the latex sample from the mass of latex in the density bottle and the known volume of the density bottle.5 Instruments5.1 Density bottle (specific gravity bottle) The capacity is 50 mL, with a ground glass stopper, a capillary passing through the stopper, and a ground glass cover (see Figure 1). ......Tips & Frequently Asked Questions:Question 1: How long will the true-PDF of GB/T 17821-2025_English be delivered?Answer: Upon your order, we will start to translate GB/T 17821-2025_English as soon as possible, and keep you informed of the progress. The lead time is typically 1 ~ 3 working days. The lengthier the document the longer the lead time.Question 2: Can I share the purchased PDF of GB/T 17821-2025_English with my colleagues?Answer: Yes. 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