Rubber temperature retraction test

ISO 2921 1997 Rubber, vulcanized - Determination of low-temperature characteristics -Temperature-retraction procedure (TR test)... 

Low-temperature properties D1329 Evaluating rubber property— retraction at lower temperatures (TR test) 9.01... 

ASTM D1329-08, Standard Test Method for Evaluating Rubber Property — Retraction at Lower Temperatures (TR Test) (Philadelphia, 2008)... 

Temperature Retraction - This test (ASTM D-1329) can be used to measure viscoelastic properties of elastomers and rubber-like materials at low temperatures, and also to evaluate crystallization effects. The test specimen is stretched to a specified elongation and frozen at -70°C (-94°F). Then, it is gradually warmed until it begins to retract toward its unstretched dimensions. The temperature at which the specimen retracts 10% has been found to correlate with brittleness temperature. 

One method for determining the state of cure of a mbber compound. A sample of the rubber is stretched, cooled to a temperature of around -70 °C while stretched and then released. As the temperature rises the mbber retracts and the T-50 value is the temperature at which it has lost 50% of its original elongation. The T-50 test is now obsolescent. 

Correlations have been established between TIO (the temperature at which 10% retraction occurs) and brittleness temperature for broadly similar rubbers and between T70 and low-temperature compression set. The test can also be adapted to give a measure of crystallization. 

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