ISO 248-1:2021 ゴム、生—揮発性物質含有量の測定—パート1：ホットミル法とオーブン法 | ページ 2

Foreword

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This document was prepared by Technical Committee ISO/TC 45, Rubber and rubber products, Subcommittee SC 3, Raw materials (including latex) for use in the rubber industry.

This second edition cancels and replaces the first edition (ISO 248-1:2011), which has been technically revised.

The main changes compared to the previous edition are as follows:

• 6.2.1, update of the tolerance temperature of the oven;
• 6.3.1 and 6.3.2, update of the procedure: mass of the test sample, drying of the test portion, temperature, requirements on the aluminium tray;
• update of the formulae;
• Annex B, update of the homogenization procedure for natural rubber;
• Annex C, addition of the precision data from an ITP conducted in 2020 for natural rubber.

A list of all parts in the ISO 248 series can be found on the ISO website.

1 Scope

This document specifies two methods for the determination of volatile-matter content in raw rubbers by using a hot mill or an oven.

These methods are applicable to the determination of the volatile-matter content in the “R” group of rubbers listed in ISO 1629. These are rubbers having an unsaturated carbon chain, for example natural rubber and synthetic rubbers derived at least partly from di-olefins. These methods can also be applicable to other raw rubbers, but in these cases it is necessary to demonstrate that the change in mass is due solely to loss of actual volatile matter and not to rubber degradation.

The hot-mill method is not applicable to natural rubber, to synthetic rubbers which are too difficult to handle on a hot mill or to synthetic rubbers in powder or chip form.

The two methods do not necessarily give identical results. Therefore, in the case of dispute, the oven method, procedure A, is the reference method.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content constitutes requirements 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.

3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 1795 and the following apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

Bibliography