Rubber, raw natural, and rubber latex, natural
— Determination of nitrogen content
(ISO 1656:2019, IDT)
This document specifies a macro-method and a semi-micro method for the determination of nitrogen in
raw natural rubber and in natural rubber latex using variants of the Kjeldahl process.
NOTE The determination of nitrogen in natural rubber is usually carried out in order to arrive at an
estimate of the protein content. Minor amounts of non-proteinous nitrogen containing constituents are also
present. However, in the dry solids prepared from natural rubber latex, these materials can make a substantial
contribution to the total nitrogen content.
