IS 11720 : Part 5 : 1993 Methods of test for synthetic rubber Part 5 : Determination of ash

1 Scope

1.1 This standard prescribes two methods for the determinationof ash from raw synthetic rubbers, compounded rubbers andvulcanizates.

This standard does not cover the interpretation of the ashresults as to the inorganic chemical content of a compound or thevulcanizate. This is the responsibility of the analyst, who has tobe aware of the behaviour of rubber additives at elevatedtemperatures.

1.2 Method A should not be used for compounded or vulcanizedrubbers containing chlorine, bromine or iodine.

1.3 Method B should not be used for uncompounded rubbers.

1.4 Lithium and flourine compounds react with silica cruciblesto form volatile compounds, giving low ash results. Thus platinumcrucibles have to be used for ashing flourine containing andlithium polymerized rubbers.

1.5 The two methods of ashing do not give identical results inall cases, hence it is necessary to state in the test report themethod of ashing employed.

2 References

IS 5599 :1970 Rubber, raw natural and synthetic -Methods forsampling and sample preparation

IS 11720 : Part 4 :1993 Methods of test for synthetic rubber :Part 4Determination of volatile matter