PA - Viscosity Number - ISO 307

The PSL Rheotek RPV-2 determins the viscosity number of polyamides in dilute solution using glass capillary viscometers in accordance with ISO 307.

The test method requires a 0.5% concentration. Solvent and solution flow times are measured at 25 deg. C using the same size of suspended-level Ubbelohde type viscometer for both measurements.

For Formic Acid a size 1 viscometer is used and a size 2 for Sulphuric Acid or m-Cresol. The method requires that two successive flow times are obtained within a 0.25% precision.

For each polyamide sample, ISO 307 also requires at least two determinations of the viscosity number in order to meet the repeatability criteria.

The dual position RPV-2 (2) is an ideal configuration as well as the four position RPV-2 (4). The iSP-1 Sample Preparation system can be used in conjunction with the RPV-2 to prepare samples on a precise weight to weight basis. Dissolution is carried out either using a wrist action shaker (WAS) for samples dissolved in Formic Acid or Sulphuric Acid and a reaction block with stirring and heating at 90 to 100 deg. C with a programmable timer. (SD-BM).