GB/T 9349-2002 in English

《GB/T 9349-2002聚氯乙烯、相关含氯均聚物和共聚物及其共混物热稳定性的测定 变色法》由TC15（全国塑料标准化技术委员会）归口，TC15SC7（全国塑料标准化技术委员会聚氯乙烯树脂产品分会）执行，主管部门为中国石油和化学工业联合会。
本标准规定了以聚乙烯均聚物和共聚物（以下简称PVC）为主的共混物和制品，通过以薄片形式放置在高温中发生变色程度测定热稳定性的两种方法。本标准适用于测定PVC的热降解阻力，通过在标准条件下不同加热时间颜色变化来评价，结果只是相对的，不适用对有颜色PVC材料的测定。――A法：油浴法――B法：烘箱法由两种方法得出的稳定时间可能不一致，不能将两个结果直接对比。

Scope

This standard specifies two methods for measuring the thermal stability of blends and products mainly composed of vinyl chloride homopolymers and copolymers (hereinafter referred to as PVC) by discoloration in the form of thin sheets placed at high temperatures. This standard is applicable to the determination of the thermal degradation resistance of PVC. It is evaluated by the color change of different heating times under standard conditions. The results are only relative and are not applicable to the determination of colored PVC materials. ——Method A: oil bath method——Method B: oven method The stability times obtained by the two methods may be inconsistent, and the two results cannot be directly compared.