ASTM D 4620 - 02 (Reapproved 2017) Standard Test Method for Evaluating the Effective Surface Area of Zinc Oxide in Rubber

Current edition approved Feb. 1, 2017. Published February 2017. Originally approved in 1986. Last previous edition approved in 2012 as D4620 – 02 (2012). — 2 p.
This test method specifies the standard materials, mixing procedure, and test method for ranking zinc-oxide samples according to their specific surface area in a standard test formula based on chloroprene rubber (CR).
The ranking is based on the cure time of the standard CR formulation.
The accurate surface area cannot be determined by this test method, since factors other than surface area may influence the cure times to some extent (for example acidity, heavy metal traces, etc.).