1.1 本试验方法包括通过红外分光光度法测定聚乙烯中的甲基（即共聚单体含量）。本试验方法适用于密度大于900 kg/m的乙烯与1-丁烯、1-己烯或1-辛烯的共聚物 3. . 不包括高压低密度聚乙烯（LDPE）和三元共聚物。 1.2 以国际单位制表示的数值，基于 IEEE/ASTM SI-10 ，将被视为标准。 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。 注1: 没有已知的ISO等效于本标准。 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====== 5.1 该方法测定乙烯与1-丁烯、1-己烯或1-辛烯共聚物中的支链数（即共聚单体含量）。这些信息可以与物理性质（如熔点、密度和刚度）相关，所有这些都取决于聚合物的结晶度。 因此，共聚单体含量的差异可能对由这些树脂制成的产品的最终性能产生重大影响。

1.1 This test method covers the determination of methyl groups (that is, comonomer content) in polyethylenes by infrared spectrophotometry. The test method is applicable to copolymers of ethylene with 1-butene, 1-hexene, or 1-octene having densities above 900 kg/m 3 . High-pressure low-density polyethylenes (LDPE) and terpolymers are excluded. 1.2 The values stated in SI units, based on IEEE/ASTM SI-10 , are to be regarded as the 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. Note 1: There is no known ISO equivalent to this standard. 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 ====== 5.1 This method determines the number of branches (that is, comonomer content) in copolymers of ethylene with 1-butene, 1-hexene or 1-octene. This information can be correlated with physical properties such as melting point, density, and stiffness, all of which depend on the degree of crystallinity of the polymer. Differences in the comonomer content thus can have a significant effect on the final properties of products made from these resins.