Historical
ISO 2930:2009
Rubber, raw natural - Determination of plasticity retention index (PRI)
ISO 2930:2009 specifies a method for determining the plasticity retention index (PRI) of raw natural rubber.
The PRI is a measure of the resistance of raw natural rubber to thermal oxidation. A high resistance to thermal oxidation is shown as a high value of the index.
International Organization for Standardization [iso]