GB/T 34247.1-2017Determination of the unsaturation of isobutene-isoprene rubber—Part 1: Iodometry (English PDF)

1 Scope

This part of GB/T 34247 specifies the determination of isobutylene - isoprene rubber (IIR) [commonly known as butyl rubber (IIR)] using the iodometric method

Unsatisfactory method.

This section applies to IIR raw rubber.

Note. This section and GB/T 34247 Part 2 may get different measurement results.

2 Normative references

The following documents for the application of this document is essential. For dated references, only the dated version applies to this article

Pieces. For undated references, the latest edition (including all amendments) applies to this document.

GB/T 601 chemical reagent standard titration solution preparation

Laboratory use specifications and test methods for analysis GB/T 6682-2008

GB/T 8170 rounded repair rules and limit values of the representation and judgment

GB/T 15340 natural, synthetic raw gum sampling and sample preparation methods

3 Method summary

Under specified conditions, a certain amount of IIR sample is dissolved in carbon tetrachloride, and iodine bromide solution is added thereto to react with it. Unreacted bromination

Iodine by adding an excess of potassium iodide solution with the reaction of iodine. Using sodium thiosulfate standard titration solution titration of the generated iodine, at the same time

Make a blank experiment. The iodine value was calculated and converted to unsaturation by empirical formula.

4 Reagents and materials

Unless otherwise specified, only reagents identified as analytical grade and grade 3 water specified in GB/T 6682-2008 are used in the analysis.