1.1 本规程涵盖了聚对苯二甲酸乙二醇酯（PET）薄片中聚氯乙烯（PVC）污染的四种分离和定性鉴定程序。 注1: 尽管没有作为定量方法提出，但本实践中提出的程序可用于提供用户自行决定的定量结果。用户有责任验证定量结果的再现性。来自独立来源的数据表明，基于454g的原始样品重量，PVC检测水平为200ppm（w/w）。 1.2 程序A 基于当这些聚合物暴露于紫外线（UV）光时PVC和PET的不同荧光。 1.3 程序B 是一种基于在235°C的空气中加热时PVC烧焦的烘箱测试。 1.4 程序C和D 是基于PVC和PET的差异染色的染色测试。 注2: 其他聚合物（例如PETG）也会吸收污渍或增白剂。这种干扰将导致PVC作为污染物的假阳性识别。 1.5 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。 有关具体危险，请参阅第节 8. . 注3: 目前还没有与该标准等效的ISO。 1.6 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 回收PET薄片中即使存在低浓度的PVC，也会导致加工过程中的设备腐蚀问题。聚氯乙烯污染水平应决定二次产品中使用回收聚合物的市场。本实践中介绍的程序用于识别回收PET薄片中的PVC污染。 注4: 这些程序也可用于估计聚氯乙烯污染的浓度。

1.1 This practice covers four procedures for separation and qualitative identification of poly(vinyl chloride) (PVC) contamination in poly(ethylene terephthalate) (PET) flakes. Note 1: Although not presented as a quantitative method, procedures presented in this practice may be used to provide quantitative results at the discretion of the user. The user assumes the responsibility to verify the reproducibility of quantitative results. Data from an independent source suggest a PVC detection level of 200 ppm (w/w) based on an original sample weight of 454 g. 1.2 Procedure A is based on different fluorescence of PVC and PET when these polymers are exposed to ultraviolet (UV) light. 1.3 Procedure B is an oven test based upon the charring of PVC when it is heated in air at 235°C. 1.4 Procedures C and D are dye tests based on differential staining of PVC and PET. Note 2: Other polymers (for example, PETG) also absorb the stain or brightener. Such interferences will result in false positive identification of PVC as the contaminant. 1.5 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. For specific hazards see Section 8 . Note 3: There is no known ISO equivalent to this standard. 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 Presence of even low concentrations of PVC in recycled PET flakes results in equipment corrosion problems during processing. The PVC contamination level shall dictate the market for use of the recycled polymer in secondary products. Procedures presented in this practice are used to identify the PVC contamination in recycled PET flakes. Note 4: These procedures may also be used to estimate the concentration of PVC contamination.