【国外标准】 Standard Test Method for Polyurethane Raw Materials: Determination of Unsaturation of Polyols

5.1 This test method is suitable for quality control, as specification tests, and for research.5.2 Side reactions that form unsaturated compounds in polypropylene oxides produce small amounts of polymers with only one hydroxyl group per chain. These unsaturated polymers lower functionality and molecular weight, while broadening the overall molecular-weight distribution.1.1 This test method measures unsaturation in polyether polyols. (See Note 1.) It uses 2 mL of ca. 0.05 M mercuric acetate reagent in methanol and about 1 g of sample or less. This test method uses a potentiometric determination of an end point.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 Mercury has been designated by many regulatory agencies as a hazardous substance that can cause serious medical issues. Mercury, or its vapor, has been demonstrated to be hazardous to health and corrosive to materials. Caution should be taken when handling mercury and mercury containing products. See the applicable product Safety Data Sheet (SDS) for additional information. Users should be aware that selling mercury and/or mercury containing products into your state or country may be prohibited by law.1.4 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.NOTE 1: This standard is equivalent to ISO 17710.1.5 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.