ISO/DIS 20163:2016 pdf free.Vulcanized rubber一Determination of free sulfur by gas chromatography [GC) and high performance liquid chromatography (HPLC). This document specifies chromatographic methods of determination of the Inorganic free sulfur (Sx) not consumed during the vulcanization of the rubber. NOTE 1 The amount of free sulfur is generally very low in a vulcanized rubber. Its direct determination by HPLC is possible, which is not the case with GC without prior derivatization. NOTE 2 In this document ‘free sulfur” is used instead of”inorganic free sulfur”. NOTE 3 The residual curing agent containing sulfur is not concerned by this measure. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 1407, Rubber — Determination of solvent extract 3 Principle The free sulfur is quantified following two experimental procedures: GC / MS or FID (Method A) and HPLC / UV (Method B). Methods A and B give identical results for the same sample. A sample of vulcanized rubber is first extracted using an appropriate solvent according to…