English to French Tech/Engineering Manufacturing Instrument - PRI Testing

Median est utilisé ci-dessous et dans l'équation PRI : PRI =(Median P30/Median P0) * 100...

Plasticity retention of raw natural rubber gives an indication of its’ heat and/or oxidation stability. Generally, the higher the plasticity value of a sample the better the ageing properties. The PRI value is the ratio of the plasticity of the cured and uncured samples, expressed as a percentage. The higher the PRI value the lower the effect of curing and therefore the higher the resistance of the rubber to oxidation.
The O14 Ageing Chamber facilitates the curing of the samples for PRI testing. The test procedure starts when the oven has recovered to test temperature after insertion of the sample drawers to the oven. After the test time is up the O14 will indicator to remove the samples from the oven.
The PRI is calculated from the below equation, where P0 is the uncured plasticity and P30 is the cured plasticity. Generally three samples are tested for each and the median value is used.