【国外标准】 Standard Test Method for Determination of Ethoxyl or Hydroxyethoxyl Substitution in Cellulose Ether Products by Gas Chromatography

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, electronic integrator, column, syringe, reaction vials, caps, heating block, and a cover. The following reagents are as follows: iodoethane, O-xylene, toluene, hydrochloric acid, and colume packing. When a cellulose ether containing ethyl or hydroxyethyl substitutes is allowed to react with hydriodic acid, one mole of iodoethane is liberated for each mole of ethoxyl or hydroxyethoxyl ether substituted on the cellulose chain. The iodoethane is extracted in-situ with o-xylene and quantitated by gas chromatography using an internal standard technique. It is recommended to run duplicate samples.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 regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Section 5 and 9.1.8.1.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.