GB/T 8290-2026Rubber latex - Sampling (English PDF)

Foreword

This document conforms to GB/T 1.1-2020 "Standardization Work Guidelines Part 1: Structure and Drafting Rules of Standardization Documents".

Drafting is scheduled.

This document supersedes GB/T 8290-2021 "Latex Sampling" and GB/T 24130-2009 "Latex Sampling for Flexible Packaging".

The document is based on GB/T 8290-2021 and incorporates content from GB/T 24130-2009.Compared to GB/T 8290-2021, except...

Aside from structural adjustments and editorial changes, the main technical changes are as follows.

a) The scope has been changed (see Chapter 1, Chapter 1 in the 2021 edition);

b) The terms "unit" and "unit sample" have been added (see 3.1, 3.4);

c) The speed of the electric mixer has been changed (see 5.1.2.2, 5.2.2 in the 2021 version);

d) A sampling instrument for flexible packaging latex has been added (see 5.2);

e) A method for "sampling from flexible packaging" has been added (see 6.6);

f) The labeling of laboratory samples and specimens has been changed (see Chapter 7, 2021 edition).

This document is modified to adopt ISO 123:2001 "Latex sampling".

Compared with ISO 123:2001, this document has undergone the following structural adjustments.

--Two terms, "unit" and "unit sample", have been added to the terminology and definitions section, and their order has been adjusted (see 3.1 and 3.4).

--Added "Sampling instruments for latex in drums, tank trucks and storage tanks" (see 5.1), incorporated into ISO 123:2001.

The introduction to Chapter 5, the content of Sections 5.1 and 5.2 have been revised, and a "General Requirements" section (see 5.1.1) has been added, with the order of the items adjusted.

--The content following "sampling device for latex in tank trucks or storage tanks" is consolidated into one item (see 5.1.3.2.1).

-- Added "Sampling from flexible packaging" to "Sampling" (see 6.6);

--6.7 corresponds to 6.5.5 of ISO 123:2001;

--6.8 corresponds to 6.6 in ISO 123:2001.

The technical differences between this document and ISO 123:2001, and the reasons therefor, are as follows.

--The scope of application of the document has been changed (see Chapter 1) to include sampling of latex for flexible packaging such as container liquid bags, in order to suit...

In response to the need for new packaging methods for latex;

--The terms "unit" and "unit sample" (see 3.1, 3.4) have been added to accommodate the new packaging methods for latex;

--The term "testing part" (see 3.5 of ISO 123:2001) has been deleted because it does not appear in the text;

--ISO 3310-1 (see 3.7, 5.5) has been replaced with the normatively referenced GB/T 6003.1 to accommodate my country's standards for woven wire mesh.

Requirements for test sieves;

--ISO 706 (see 3.7, 6.7) has been replaced with the normatively referenced GB/T 8291 to adapt to my country's standards for latex curd content (screen residue).

Requirements for the determination of (substances);

--Change the introductory text in "Instruments" to the clause in "General Requirements" (see 5.1.1) because it contains requirements;

--The requirements for "stirrer" and "sampling device" are changed to two items in the "General Requirements" (see 5.1.1.2 and 5.1.1.3), because...

These are general requirements;

-- Changed the "Electric Stirrer Speed" from "50 r/min~200 r/min" to "48 r/min~201 r/min" (see...) 5.1.2.2), to correct the error in the approximate upper and lower limits of the electric mixer speed range;

--ISO 15528 (see 5.1.3.2.2) has been replaced with the normatively referenced GB/T 3186 to adapt to my country's standards for paints, varnishes, and...

Requirements for sampling raw materials used in paints and varnishes;

need;

--ISO 124 (see 6.5.3) has been replaced with the normatively referenced GB/T 8298 to accommodate my country's standards for the determination of total solids content in latex.

Requirements;

--The labeling of laboratory samples and specimens has been changed (see Chapter 7) to accommodate the new packaging method for latex.

The following editorial changes have been made to this document.

--An introduction has been added;

--Added Appendix A (informative) with images of containers containing flexible packaging latex.

Please note that some content in this document may involve patents. The issuing organization of this document assumes no 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 Standardization of Rubber and Rubber Products (SAC/TC 35).

Introduction

With continuous technological advancements, the transportation packaging of latex has evolved from traditional drums and cans to a flexible packaging format.

To accommodate container shipping, this packaging is called a container liquid bag.

Latex sampling

Warning – Users of this document should have prior experience working in a formal laboratory setting. This document does not cover all possible safety precautions.

Problem. Users are responsible for taking appropriate safety and health measures and ensuring compliance with relevant national regulations.

1 Scope

This document describes the sampling procedures for concentrated natural latex, synthetic latex, and artificial latex.

This document applies to flexible packaging latex, including latex in drums, tank trucks, storage tanks, and container liquid bags (see Appendix A).

Sampling. The sampling procedure can also be used for sampling plastic dispersions.

2 Normative references

The contents of the following documents, through normative references within the text, constitute essential provisions of this document. Dated citations are listed below.

For references to documents, only the version corresponding to that date applies to this document; for undated references, the latest version (including all amendments) applies.

This document.

GB/T 3186 Sampling of raw materials for paints, varnishes and paints and varnishes (GB/T 3186-2006, ISO 15528:2000) IDT GB/T 6003.1 Technical requirements and inspection of test sieves - Part 1: Metal wire woven mesh test sieves (GB/T 6003.1-2022, ISO 3310-1:2016, MOD) GB/T 8291 Determination of latex curd content (sieve residue) (GB/T 8291-2023, ISO 706:2004, MOD) GB/T 8298 Determination of total solids content in latex (GB/T 8298-2017, ISO 124:2014, MOD)

3 Terms and Definitions

The following terms and definitions apply to this document.

unit

Pre-packaged container liquid bags.

batch lot

A certain quantity of latex that is considered to be processed or produced under the same conditions.

Note. A batch of latex may be contained in one or more containers.

sample

A certain amount of latex extracted from a batch of latex.

unit sample

A certain amount of latex representing one unit is extracted from a unit.