1.1 本标准试验方法涵盖了通过高效液相色谱法（HPLC）测定橡胶中可萃取2-巯基苯并噻唑（MBT）的程序，以评估其生物利用度。 1.2 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.3 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户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。 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）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》中确立的国际公认标准化原则制定的。 ====意义和用途====== 4.1 MBT通常用作橡胶和乳胶制品的硫化促进剂。当橡胶长时间接触人类皮肤或粘膜时，测定固化橡胶中的MBT对于评估这种有害物质释放的风险很重要。 4.2 当在化合物中使用苯并噻唑磺酰胺作为促进剂时，MBT新形成的MBT可能在硫化过程中产生，因此，它是硫化橡胶中MBT总含量的一部分。 4.3 MBT作为原料的纯度可以通过以下测试方法进行评估 D1991 基于MBT与氢氧化钠的电位滴定。 4.4 MBT也是MBT中的主要杂质。虽然MBT在任何有机溶剂中都微溶，但MBT非常易溶。MBT中作为原料的MBT含量可根据试验方法确定 D5044 . 4.5 该测试方法可作为质量控制工具，也可用于研究和开发工作。

1.1 This standard test method covers a procedure for the determination of extractable 2-Mercaptobenzothiazole (MBT) in rubber by high performance liquid chromatography (HPLC) to assess its bioavailability. 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. 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. ====== Significance And Use ====== 4.1 MBT is commonly used in rubber compounding as a curing accelerator for rubber and latex products. The determination of MBT in cured rubber is important to assess the risk of a release of this hazardous substance when rubber is in prolonged contact with human skin or mucous membranes. 4.2 Neo-formed MBT from MBTS might be created during the process of vulcanization when benzothiazolesulfenamides are used in the compound as accelerators, and therefore, it is part of the total MBT content in the cured rubber. 4.3 The purity of MBT as raw material can be evaluated by following Test Method D1991 based on a potentiometric titration of MBT with sodium hydroxide. 4.4 MBT is also a major impurity in MBTS. While MBTS is sparingly soluble in any organic solvent, MBT is very soluble. The amount of MBT contained in MBTS as raw material can be determined according to Test Method D5044 . 4.5 This test method may be used as a quality control tool as well as for research and development work.