ISO 2028 pdf download

ISO 2028 pdf download.Synthetic rubber latex — Preparation of dry polymer 1 Scope This International Standard specifies four methods for the isolation of dry polymer from synthetic polymer latices con- taining anionic surfactants, for the purpose of subsequent testing. Tests that may be performed include the determi- nation 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 that are used in the manufacture of synthetic rubber latices, no one method is suitable for all latices. The methods given in this International Standard are suitable for a wide variety of latices, but their applicability should be confirmed for individual types. Latices containing non-ionic stabiliz- ers, in particular, may be resistant to coagulation. These methods are not necessarily suitable, without modification, for latices containing polymers having high tack. It should be noted that the dry polymer as isolated may contain residual organic acids or their aluminium salts which may affect the properties of the polymer. This should be taken into account when performing analytical tests. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. For dated references, subsequent amendments to, or revisions of, any of these publica- tions do not apply. However, parties to agreements based on this International Standard are encouraged to investi- gate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 1 23:— 1 ) , Rubber latex — Sampling . ISO 1 24:1 997, Latex, rubber — Determination of total solids content . 3 Principle The latex is coagulated in the presence of an antioxidant, using different procedures depending on the type of latex. 4 Reagents During the preparation of the reagent solutions and the isolation of the polymer, use only distilled water or water of equivalent purity. 4.1 Coagulant A: An aqueous solution of a polyamine polyelectrolyte, prepared by dissolving of polyamine polyelectrolyte in of hot, water and then diluting the resultant solution to . NOTE 1 Suitable polyamine polyelectrolytes include “Prodefloc CRC 300C” (CAS No. 42751 -79-1 ) available from Industrie Chimiche Caffara SpA, Casella postale 327, 251 00 Brescia, Italy, and “EPI DNA” available from...