1.1 本试验方法规定了使用含氟聚合物的差示扫描量热法（DSC）的条件。它涵盖了使用DSC分析含氟聚合物、PTFE、PVDF、PCTFE和PVF及其共聚物PFA、MFA、FEP、ECTFE、EFEP、VDF/HFP、VDF/TFE/HFP、VDF/CTFE。本试验方法适用于分析粉末以及从半成品或成品中提取的样品。含氟聚合物的性质是，运行DSC分析和解释结果需要特殊程序。 1.2 以国际单位制表示的数值详见 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: 目前没有复制此测试方法的ISO标准。ISO 20568-1和ISO 20568-2涵盖了类似的测试，并在测试条件下参考了本测试方法。 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 DSC分析可用于含氟聚合物，以实现至少四个不同的目标，如下所示: 4.1.1 测量转变温度，以帮助识别各种含氟聚合物，单独或在混合物中； 4.1.2 通过测量熔融热，比较含氟聚合物样品的两个或多个样品相对于另一个样品的结晶含量的相对水平； 注2: 在完全结晶聚合物的熔融热值可用之前，无法确定结晶含量的绝对值。 4.1.3 纯PTFE均聚物的结晶热取决于试样的相对分子量。一些PTFE树脂用少量共聚单体进行改性。这些改性对结晶行为有深远影响，在评估结果时应予以考虑。 4.1.4 表征PTFE（在从未熔化的PTFE粉末或产品上测定的DSC热曲线传达了有关形态和分子结构细节的可观信息）； 4. 4.1.5 补充规范中所述的标准比重（SSG）测试 D4894 和 D4895 通过使用纯PTFE均聚物的结晶热，取决于试样的相对分子量。 然而，这些规范的范围包括用少量共聚单体改性的PTFE树脂，许多商用PTFE树脂都是以这种方式改性的。这些修饰可以对结晶行为产生深远的影响。已发布的关系 4. 结晶热和分子量之间是指纯PTFE均聚物，因此不能应用于改性树脂。

1.1 This test method defines conditions for the use of differential scanning calorimetry (DSC) with fluoropolymers. It covers the use of DSC analyses with the fluoropolymers, PTFE, PVDF, PCTFE, and PVF and their copolymers PFA, MFA, FEP, ECTFE, EFEP, VDF/HFP, VDF/TFE/HFP, VDF/CTFE. The test method is applicable to the analysis of powders as well as samples taken from semi-finished or finished products. The nature of fluoropolymers is such that special procedures are needed for running DSC analysis and interpreting the results. 1.2 The values stated in SI units as detailed in 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 currently no ISO standard that duplicates this test method. ISO 20568-1 and ISO 20568-2 cover similar testing and reference this test method for testing conditions. 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 DSC analysis may be used with fluoropolymers to achieve at least four different objectives as follows: 4.1.1 To measure transition temperatures to aid in the identification of the various fluoropolymers, individually or in mixtures; 4.1.2 To compare the relative levels of crystalline content of two or more specimens of a sample of a fluoropolymer relative to another sample by measuring the heat of fusion; Note 2: Absolute values of crystalline content cannot be determined until values for heats of fusion of the completely crystalline polymers are available. 4.1.3 The heat of crystallization of pure PTFE homopolymer is depending on the relative molecular weight of the specimen. Some PTFE resins are modified with small amounts of comonomers. These modifications have profound effects on crystallization behavior and shall be considered when evaluating the results. 4.1.4 To characterize PTFE (DSC thermal curves determined on powders or products of PTFE that have never been melted convey appreciable information about details of morphology and molecular structure); 4 4.1.5 To supplement the test for standard specific gravity (SSG) described in Specifications D4894 and D4895 by using the heat of crystallization of pure PTFE homopolymer, depending on the relative molecular weight of the specimen. The scopes of these specifications, however, include PTFE resins modified with small amounts of comonomers, and many commercial PTFE resins are modified in this manner. These modifications can have profound effects on crystallization behavior. Published relationships 4 between heat of crystallization and molecular weight refer to pure PTFE homopolymers and, therefore, cannot be applied to the modified resins.