1.1 This test method is applicable to the determination of ethoxyl or hydroxyethoxyl substitution in cellulose ether products by a Zeisel gas chromatographic technique. 1.2 The values stated in SI units are to be regard This test method is applicable to the determination of ethoxyl or hydroxyethoxyl substitution in cellulose ether products by a Zeisel gas chromatographic technique. The equipment and materials to be used shall include reagents, gas chromatograph, elect