1.1 本试验方法包括用气相色谱法测定AMS（α-甲基苯乙烯）的纯度。气相色谱系统的校准通过外部标准校准技术完成。 1.2 本试验方法适用于异丙苯、3-甲基-2-环戊烯-1-酮、， n -丙苯， tert公司 -丁基苯， 证券交易委员会 -丁基苯， cis公司 -2-苯基-2-丁烯，苯乙酮，1-苯基-1-丁烯，2-苯基-2-丙醇， trans公司 -2-苯基-2-丁烯， m -异丙基甲苯， p -异丙苯和苯酚，这是AMS制造过程中常见的。该方法也适用于测定通常作为稳定剂添加到AMS中的对叔丁基邻苯二酚（TBC或PTBC）。通过这种方法，AMS中的杂质可以在5到800 mg/kg的范围内进行分析。（见表2。）根据ASTM研究报告RR中的结果: D16-1022，总结在表2中，这些杂质的定量限平均为4 mg/kg，而检测限平均为1.2 mg/kg 毫克/千克。 1.3 在使用该方法确定测试结果是否符合适用规范时，应根据修约方法对结果进行修约 E29年 . 1.4 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。 1.5 本标准无意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。 有关具体的危险说明，请参阅第节 8. . 1.6 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====== 5.1 本试验方法适用于对参考材料设定规范 1.2 并用作生产AMS或在制造过程中使用AMS的内部质量控制工具。它也可用于涉及自动测量系统的开发或研究工作。 5.2 本试验方法有助于测定含有正常杂质的AMS的纯度。如果AMS中存在极高沸点或异常杂质，则该测试方法不一定检测到它们，纯度计算将是错误的。

1.1 This test method covers the determination of the purity of AMS (α-methylstyrene) by gas chromatography. Calibration of the gas chromatography system is done by the external standard calibration technique. 1.2 This test method has been found applicable to the measurement of impurities such as cumene, 3-methyl-2-cyclopentene-1-one, n -propylbenzene, tert -butylbenzene, sec -butylbenzene, cis -2-phenyl-2-butene, acetophenone, 1-phenyl-1-butene, 2-phenyl-2-propanol, trans -2-phenyl-2-butene, m -cymene, p -cymene, and phenol, which are common to the manufacturing process of AMS. The method has also been found applicable for the determination of para-tertiary-butylcatechol (TBC or PTBC) typically added as a stabilizer to AMS. The impurities in AMS can be analyzed over a range of 5 to 800 mg/kg by this method. (See Table 2.) Based on the results in ASTM Research Report RR:D16-1022, summarized in Table 2, the limit of quantitation for these impurities averages 4 mg/kg, while the limit of detection averages 1.2 mg/kg. 1.3 In determining the conformance of the test results using this method to applicable specifications, results shall be rounded off in accordance with the rounding-off method of Practice E29 . 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 This standard does not purport to address all 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 8 . 1.6 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 This test method is suitable for setting specifications on the materials referenced in 1.2 and for use as an internal quality control tool where AMS is produced or is used in a manufacturing process. It may also be used in development or research work involving AMS. 5.2 This test method is useful in determining the purity of AMS with normal impurities present. If extremely high boiling or unusual impurities are present in the AMS, this test method would not necessarily detect them and the purity calculation would be erroneous.