BS ISO 289-2:2020 pdf free.Rubber, unvulcanized —Determinationsusing a shearing-disc viscometer.
This document specifies a method for determining the pre-vulcanization characteristics ofcompounded rubber.
The pre-vulcanization characteristics determined by this method provide a means of estimating howlong compounded rubber can be maintained at high temperatures and remain processable.
The following documents are referred to in the text in such a way that some or all of their contentconstitutes requirements of this document. For dated references,only the edition cited applies.Forundated references, the latest edition of the referenced document (including any amendments) applies.ISO 289-1,Rubber,unvulcanized – Determinations using a shearing-disc viscometer – Part 1:Determination of Mooney viscosity
For the purposes of this document, the following terms and definitions apply.
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The test consists of determining how the Mooney viscosity of the rubber compound changes withrunning time at a specified temperature relevant to the process for which the compound is to be used.The time at which the Mooney viscosity has increased by a specified number of units is recorded.
The apparatus specified in IS0 289-1 shall be used. lt is permissible to use the small rotor for high-viscosity compounds.
Prepare the two discs comprising the test specimen from a sheet of rubber compound, using theprocedure for preparation of test pieces described in ISO 289-1.Choose a test temperature relevant to the process for which the compound is to be used.
Use the procedure described in ISO 289-1.The pre-heating time shall be 1 min, and the test shallbe continued until the viscosity reaches the specified number of units above the minimum. When alarge rotor is used, the increase is specified as five units and when a small rotor is used, the increaseis specified as three units. The corresponding pre-vulcanization times are designated t; and t,respectively.A typical trace obtained with the large rotor is shown in Figure 1.BS ISO 289 pdf download.