Ash content gives an estimate of the inorganic content of cellulose ester samples. The presence of high levels of inorganic content (ash) can be detrimental to the melt stability and optical clarity of a cellulose ester in melt processing or act as a potential source of insolubles when the ester is used in solution.

1.1 These test methods cover procedures for the testing of cellulose acetate propionates and acetate butyrates. These esters may vary widely in composition and properties, so certain of the procedures can be used only in the ranges of composition where they are suitable.

1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.