1.1 本试验方法包括通过滴定法测定乙二醇中的游离酸和乙二醇酯。 1.2 该试验方法通常用于制造发动机冷却液的二醇。它不能用于配制的发动机冷却液。抑制剂会干扰测定。 1.3 以国际单位制表示的数值应视为标准。本标准不包括其他计量单位。 1.4 本标准并不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。 1.5 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 用于生产发动机冷却液的乙二醇中存在酸或乙二醇酯是不可取的。在发动机冷却系统的条件下，酯可以水解形成二醇和酸。 酸会与腐蚀抑制剂发生反应，从而缩短冷却液的使用寿命。该方法可以测定乙二醇中存在的酸和乙二醇酯的量。

1.1 This test method covers the determination of free acids and glycol esters in glycols by titration. 1.2 This test method is typically used on glycols used for the manufacture of engine coolant. It cannot be used on formulated engine coolant. The inhibitors will interfere with the determination. 1.3 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 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. 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. ====== Significance And Use ====== 5.1 The presence of acids or glycol esters in the glycol used to produce engine coolant is undesirable. Under conditions in an engine cooling system, the esters can hydrolyze to form glycol and an acid. The acid will react with the corrosion inhibitors, thereby reducing the useful life of the coolant. This method can determine the amount of acid and glycol ester present in the glycol.