1.1 本试验方法包括测定连接在脂族化合物、环状化合物和酚中的伯碳原子和仲碳原子上的羟基，羟基数为0.5-367。它不适用于测定连接在叔碳原子上的羟基。本试验方法适用于聚缩醛、温度敏感材料、高固体聚合物多元醇和刚性多元醇。中列出的其他可用测试方法 注1 不适用于上面列出的许多样品类型。 1.1.1 该测试方法目前推荐用于中性精制产品。然而，已经成功地应用于一些含有过量酸性物质的过程中样品。 当然，必须进行适当的验证，以表明酸性物种要么没有干扰，要么已经消除了酸性物种的干扰。 注1: 试验方法中给出了测定羟基的其他方法 第817页 ， D871型 ， D4252天 ， 天4273 ， 天4274 ， 22年 ， 第326页 和 E335 。 1.2 检测限（LOD）为0.18个单位，定量限（LOQ）为0.59个单位。单位=羟基数（OH#）。 注2: LOD和LOQ使用 14.1.2.1 。 1.3 查阅当前适当的安全数据表（SDS），了解有关毒性、急救程序和安全预防措施的详细信息。 1.4 以国际单位制表示的数值应视为标准。 本标准中不包括其他计量单位。 1.5 以下内容适用于确定使用该测试方法的测试结果是否符合适用规范。应按照实践中的四舍五入方法对结果进行四舍五舍五入 第29页 。 1.6 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 有关具体危险，请参阅第节 9 。 1.7 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ====意义和用途====== 5.1 羟基是一个重要的官能团，在许多中间体和最终用途应用中需要了解其含量。该试验方法用于测定伯羟基和仲羟基，并可用于测定含有它们的化合物。 5.2 与其他羟基值方法相比，该测试方法具有以下优点:快速（10分钟），不含吡啶，环境温度低，样品量小，适用于极低的羟基值（<1），并且易于自动化。

1.1 This test method covers the determination of hydroxyl groups attached to primary and secondary carbon atoms in aliphatic and cyclic compounds and phenols from 0.5 to 367 hydroxyl number. It is not suitable for determination of hydroxyl groups attached to tertiary carbon atoms. This test method is applicable to polyacetals, temperature sensitive materials, high solids polymer polyols, and rigid polyols. Other available test methods listed in Note 1 are not suitable for many of the sample types listed above. 1.1.1 This test method is currently recommended for neutral refined products. Successful application has been made, however, to some in-process samples that contain an excess of acidic species. Proper validation must be performed, of course, to show that the acidic species either does not interfere, or that the acidic species interference has been obviated. Note 1: Other methods for determination of hydroxyl groups are given in Test Methods D817 , D871 , D4252 , D4273 , D4274 , E222 , E326 , and E335 . 1.2 The Limit of Detection (LOD) is 0.18 units and the Limit of Quantitation (LOQ) is 0.59 units. Unit = hydroxyl number (OH#). Note 2: LOD and LOQ were calculated using Standard deviations from 14.1.2.1 . 1.3 Review the current appropriate Safety Data Sheets (SDS) for detailed information concerning toxicity, first aid procedures, and safety precautions. 1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.5 The following applies for the purposes of determining the conformance of the test results using this test method to applicable specifications. Results shall be rounded off in accordance with the rounding-off method of Practice E29 . 1.6 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 hazards see Section 9 . 1.7 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. ====== Significance And Use ====== 5.1 Hydroxyl is an important functional group and knowledge of its content is required in many intermediate and end use applications. This test method is for the determination of primary and secondary hydroxyl groups and can be used for the assay of compounds containing them. 5.2 This test method has the following advantages over other hydroxyl number methods: It is rapid (10 min), pyridine-free, ambient temperature, small sample size, applicable to extremely low hydroxyl numbers (<1), and is amenable to automation.