scope:

This International Standard specifies a method for determining the viscosity number and limiting viscosity number of polyethylenes and polypropylenes at 135 ° C in dilute solution. It is applicable to low, medium and high density polyethylenes and to a wide range of polypropylenes including pure isotactic, stereoblock and atactic polymers. The viscosity of polymer solutions may be affected by additives present in the sample. The value of viscosity number determined by this method may therefore be unreliable if the sample contains fillers or other additives.