scope:

NEN-ISO 2028 specifies four methods for the isolation of dry polymer from synthetic polymer latices containing anionic surfactants, for the purpose of subsequent testing. Tests to be performed include the determination of the Mooney viscosity, the bound-styrene or acrylonitrile content in the polymer chain or the mill shrinkage. Because of the wide variety of surfactants and stabilizers used in the manufacture of synthetic rubber latices, there is not one method suitable for all latices. The methods given in this International Standard are suitable for a wide variety of latices, but their applicability is to be confirmed for individual types. Latices containing non-ionic stabilizers, in particular, may be resistant to coagulation. These methods are not necessarily suitable, without modification, for latices containing polymers having high tack. The dry polymer as isolated may contain residual organic acids or their aluminium salts which may affect the properties of the polymer and which are to be taken into account when performing analytical tests.