ISO 7780:1998 PDF

Overview

ISO 7780:1998 - Rubbers and rubber latices - Determination of manganese content - Sodium periodate photometric methods - defines two photometric procedures for measuring total manganese in raw rubbers, latices and compounded/vulcanized rubbers. Both methods oxidize manganese to permanganate with sodium periodate and determine concentration by spectrophotometric measurement at ~525 nm. The standard addresses sample preparation, reagents, instrumentation and calibration required for reliable manganese determination in elastomers.

Key Topics and Requirements

• Two validated methods
  • General method: Suitable for compounded or vulcanized rubbers, especially when samples contain heavy loadings of inert fillers (silicates, CaCO3) or ingredients that form insoluble phosphates. Involves ashing/fusion (platinum crucible or fluoroborate fusion) or acid digestion when chlorine is present.
  • Restricted method: Shorter route for raw rubbers, latices and compounds with light filler loadings (typically