Path:
Home >
GB/T >
Page504 > GB/T 45128-2025
Price & Delivery
US$679.00 · In stock · Download in 9 secondsGB/T 45128-2025: Plastics - Determination of water content
Delivery: 9 seconds. True-PDF full-copy in English & invoice will be downloaded + auto-delivered via email. See
step-by-step procedureStatus: Valid
| Std ID | Version | USD | Buy | Deliver [PDF] in | Title (Description) |
| GB/T 45128-2025 | English | 679 |
Add to Cart
|
6 days [Need to translate]
|
Plastics - Determination of water content
|
Click to Preview a similar PDF
Basic data
| Standard ID | GB/T 45128-2025 (GB/T45128-2025) |
| Description (Translated English) | Plastics - Determination of water content |
| Sector / Industry | National Standard (Recommended) |
| Classification of Chinese Standard | G31 |
| Classification of International Standard | 83.080.01 |
| Word Count Estimation | 34,343 |
| Date of Issue | 2025-01-24 |
| Date of Implementation | 2025-08-01 |
| Issuing agency(ies) | State Administration for Market Regulation, China National Standardization Administration |
GB/T 45128-2025: Plastics - Determination of water content
---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 83.080.01
CCSG31
National Standard of the People's Republic of China
Determination of moisture content in plastics
(ISO 15512.2019,MOD)
Released on 2025-01-24
2025-08-01 Implementation
State Administration for Market Regulation
The National Standardization Administration issued
Table of Contents
Preface III
Introduction IV
1 Scope 1
2 Normative references 1
3 Terms and Definitions 1
4 Sample preparation and storage 1
5 Method A---Anhydrous methanol extraction method 2
5.1 Principle 2
5.2 Test reagents 2
5.3 Test equipment 2
5.4 Test Step 2
5.5 Calculation and presentation of results 3
5.6 Precision 3
6 Method B1---Tube furnace evaporation method 3
6.1 Principle 3
6.2 Test reagents 3
6.3 Test equipment 3
6.4 Test Step 5
6.5 Calculation and presentation of results 6
6.6 Precision 6
7 Method B2---Vial Evaporation Method 7
7.1 Principle 7
7.2 Test reagents 7
7.3 Test equipment 7
7.4 Test steps 8
7.5 Calculation and presentation of results 10
7.6 Precision 10
8 Method C---Pressure Measurement Method 10
8.1 Principle 10
8.2 Reagents 11
8.3 Test equipment 11
8.4 Test steps 12
8.5 Calculation and presentation of results 14
8.6 Precision 14
9 Method D---Phosphorus pentoxide coulometric method 15
9.1 Principle 15
9.2 Reagents 15
9.3 Test equipment 15
9.4 Test steps 16
9.5 Result calculation and presentation 17
9.6 Precision 18
10 Method E---Calcium Hydride Test Method 18
10.1 Principle 18
10.2 Reagents 18
10.3 Test equipment 18
10.4 Inspection and calibration of instruments 19
10.5 Test steps 20
10.6 Precision 21
11 Test Report 21
Appendix A (Informative) Structure Number Comparison List 22
Appendix B (Informative) Optional methods for sample preparation and titration 24
B.1 General Principles24
B.2 Solution titration 24
B.3 Continuous titration in suspension 24
B.4 Discontinuous titration in suspensions 24
B.5 External extraction of water 24
Appendix C (Normative) Selection of optimal heating temperature and heating time for moisture content test 25
C.1 Optimal temperature selection 25
C.2 Interpretation of test results 25
C.3 Optimal heating time selection 25
Appendix D (Normative) Test of water content in water-containing standard materials 27
Reference 28
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.
This document is modified to adopt ISO 15512.2019 "Determination of water content of plastics".
Compared with ISO 11512.2019, this document has many structural adjustments. The structural number changes between the two documents are shown in the table below.
See Appendix A.
The technical differences between this document and ISO 15512.2019 and their reasons are as follows.
--- Adjust the operation and related explanations of the method in the scope of application of the method in Chapter 1 to the newly added introduction to increase the applicability of the standard.
Readability;
--- Adjust the provisions of the method detection limit in Chapter 1 to the calculation and expression of the results of each method (see 5.5, 6.5, 7.5, 8.5, 9.5 and
10.5.2) to meet the requirements of standard compilation;
--- Use the normative reference GB/T 6283 to replace ISO 760 (see 5.2.2, 5.3.8) to adapt to my country's technical conditions and increase operability
Sex;
--- Adjust Note 1 of ISO 15512.2019 “Pressure moisture analyzer” to the main text (see 8.3.1) to comply with the requirements for standard compilation;
--- Unify the unit of water content of nitrogen and unify it to 0.554×10-6 in accordance with the provisions of Appendix A of GB/T 5832.2-2016
(volume fraction) (see 7.2.6, 9.2.3) to increase the consistency between the standard and the Chinese standard;
--- Adjust the informative Appendix B of ISO 15512.2019 to a normative appendix (see Appendix C) to meet the requirements for standard preparation;
--- Adjust the informative Appendix C of ISO 15512.2019 to a normative appendix (see Appendix D) to meet the requirements for standard preparation.
The following editorial changes were made to this document.
--- The informative reference GB/T 1034 replaces ISO 62 (see introduction) to adapt to my country's technical conditions;
--- The informative reference GB/T 1631.1 replaces ISO 1632.1 (see C.2) to adapt to my country's technical conditions;
--- The informative reference GB/T 1631.3 replaces ISO 1632.3 (see C.2) to adapt to my country's technical conditions;
--- The informative reference GB/T 1631.4 replaces ISO 1632.4 (see C.2) to adapt to my country's technical conditions;
--- The informative reference GB/T 1631.5 replaces ISO 1632.5 (see C.2) to adapt to my country's technical conditions;
--- The informative reference GB/T 12006.1 replaces ISO 370 (see C.2) to adapt to my country's technical conditions.
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 Plastics Standardization Technical Committee (SAC/TC15).
This document was drafted by. China Bluestar Chengdu Testing Technology Co., Ltd., PetroChina Petrochemical Research Institute
Institute, Zhejiang Xinhecheng Special Materials Co., Ltd., Henghe Materials Technology Co., Ltd., Liaocheng Jinge Synthetic Materials Co., Ltd., Kingfa Technology
Co., Ltd., Huafeng Group Co., Ltd., Chongqing Yuntianhua Tianju New Materials Co., Ltd., Wanhua Chemical Group Co., Ltd., Jiangsu
Junhua Special Polymer Materials Co., Ltd., Qingdao Youpaipu Environmental Protection Technology Co., Ltd., Shandong Huacheng High-tech Adhesives Co., Ltd.
Ningbo Zhongqin Testing Technology Co., Ltd., Henan Urban Construction College, Ningbo Yufan Technology Co., Ltd., Suzhou Xuguang Polymer Co., Ltd.,
Fengte (Zhejiang) New Materials Co., Ltd., Ganzhou Suilian Engineering Plastics Co., Ltd., Dongguan Qunan Plastic Industry Co., Ltd., Changzhou Run
Bang Mould Technology Co., Ltd., Guizhou Shengyang Pipeline Technology Co., Ltd., Shenzhen Jinhuanyu Wire and Cable Co., Ltd., Zhejiang World Expo New Materials
Co., Ltd., Zhejiang Walrus New Materials Co., Ltd., Qingdao Zhongxin Huamei Plastic Co., Ltd., Jiangsu Saiou Shin-Etsu Defoamer Co., Ltd.
Company, Auribon (Xiamen) New Materials Co., Ltd.
The main drafters of this document are. Luo Xiaoxia, Liu Liuxin, Zhou Guiyang, Wang Bin, Liu Wanxing, Zheng Wen, Yao Zengwen, Pu Xuetao, Mou Guangyin, Li Jun,
Zhang Qunjia, Chen Bingshan, Ye Jiamei, Liu Xueping, Wu Beilei, Wang Haili, Wang Yongfei, Ling Lexu, Yan Xiaofeng, Deng Hangjun, Li Guodong, Gao Jianguo,
Liang Jun, Deng Linshou, Chen Ganlin, Chen Yongquan, Tu Dan, Jiang Feifei, Zhang Songlei, Chen Shihai, Wu Longjie.
Introduction
Moisture content is an important parameter for processing materials. Too high moisture content will affect the processing performance of the material.
This document describes six moisture content test methods.
---Method A is anhydrous methanol extraction method. Anhydrous methanol is used to extract water from the sample, and then the extract is subjected to Karl Fischer
Titration.
---Method B1 is a tube furnace evaporation method. The water contained in the sample is evaporated and transported to the titration cell by dry air or nitrogen, and then
The collected water was then coulometrically determined using a Karl Fischer titrator.
---Method B2 is the sample bottle evaporation method. The water contained in the sample is evaporated and transported to the titration cell by dry air or nitrogen, and then
The collected water was then subjected to Karl Fischer titration using a Karl Fischer titrator.
---Method C is a pressure measurement method. The evaporation of water in the vacuum system causes an increase in pressure, and the water content of the sample is calculated by the pressure increase.
The evaporation temperature is not specified in this document, and for the pressure method a temperature of.200°C is generally used. However, for some condensation materials
This temperature may cause condensation reaction and produce water.
---Method D is to use phosphorus pentoxide (P2O5) coulometric method. The water contained in the sample is evaporated and then transported through dry air or nitrogen.
It is sent to a phosphorus pentoxide electrolytic cell, and then the collected water is subjected to thermocoulometric determination.
---Method E is the calcium hydride test method. The sample is heated under vacuum to evaporate the water in the sample. The evaporated water reacts with calcium hydride
Hydrogen (H2) and calcium hydroxide are generated. Hydrogen (H2) increases the pressure of the vacuum system, and the sample content is calculated by the pressure increase value.
The volatile components that do not react with calcium hydride condense into liquid in the cooling trap and do not affect the determination of water content.
The water content of plastics tested by the above method is different from the water absorption of plastics tested by GB/T 1034-2008 (dynamic balance).
Performance parameters, understanding the differences between the two standards is conducive to the implementation of the standards.
The differences in sample packaging, sample handling, equipment and setting parameters will affect the test results of plastic moisture content.
The inter-laboratory comparability of moisture content determination of raw materials is usually poor. Package the samples in dry glass containers or waterproof sealed bags and place them in dry
Processing samples in a nitrogen or air environment is conducive to improving the comparability of data between laboratories. In order to improve repeatability and reproducibility, strict
Follow the test procedures specified in this document.
The optimum heating temperatures described in this document will vary depending on the material being tested, the equipment used, and actual conditions.
The water in the test material will not evaporate completely, and too high a temperature will cause degradation and condensation reactions, resulting in the generation of water.
A method for optimizing heating temperature was proposed in order to select a suitable temperature for the determination of water content and to improve the comparability among laboratories.
Determination of moisture content in plastics
1 Scope
This document describes six methods for determining the moisture content of plastic powders, granules and products. Method A, Method B, Method C and Method E are suitable for
For all types of plastics, method D is suitable for polyamide (PA), polycarbonate (PC), polypropylene (PP), polyethylene (PE), epoxy resin
Resins, polyesters, polytetrafluoroethylene (PTFE), polyvinyl chloride (PVC), polylactic acid (PLA), polyamide diamine (PAI), not suitable for releasable
Samples of NH3.
Method A (anhydrous methanol extraction method) is applicable to all samples with a size less than 4mm×4mm×3mm and a water content greater than or equal to 0.1%.
The method is accurate to 0.1%. This method can also be used to determine the powder prepolymer material that is insoluble in methanol.
Method B1 (tube furnace evaporation method) is applicable to all samples with a size less than 4 mm × 4 mm × 3 mm and a water content greater than or equal to 0.01%.
Determination of.
Method B2 (vial evaporation method) is applicable to all samples with a size less than 4 mm × 4 mm × 3 mm and a water content greater than or equal to 0.01%.
Determination of.
Method C (pressure measurement method) is applicable to the determination of water content greater than or equal to 0.01%. This method is not applicable to the determination of water containing volatile compounds.
For plastic samples containing substances (except water), volatile compounds have a significant effect on pressure at room temperature. When using method C, gas chromatography is used
Regularly check samples (especially new types or brands) for volatile compounds using methods such as
Method D [phosphorus pentoxide (P2O5) coulometric method] is applicable to the determination of water content greater than or equal to 0.01%. This method is not applicable to
Plastic samples containing volatile compounds (except water), volatile compounds [especially volatile components that can react with phosphoric acid pentoxide coating]
Regularly check samples (especially new types or grades) for volatile chemicals.
Compound.
Method E (calcium hydride test method) is applicable to the determination of water content greater than or equal to 0.001%.
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 to
This document.
GB/T 6283 Determination of water content in chemical products Karl Fischer method (general method) [GB/T 6283-2008,
ISO 760.1978,NEQ]
3 Terms and definitions
There are no terms or definitions that require definition in this document.
4.Sample preparation and storage
The sample can be in any form such as plastic powder, pellets and products.
Quickly cut large-size samples into pieces smaller than 4mm×4mm×3mm. Take a certain amount of representative samples and place them on the
Put the solution into a flask or sealed bag that has been dried to constant weight and seal the mouth of the flask immediately.
...
