塑料氧化诱导期影响因素分析及其测量不确定度评定

Influence Factor Analysis and Measurement Uncertainty Evaluation on Oxidation Induction Time of Plastics

以一种黑色聚乙烯颗粒为研究对象,依据GB/T 19466.6-2009测定样品在220℃恒温时的氧化诱导期,探讨了样品质量、恒温温度、氧气流量等参数对测定结果的影响,并依据JJF1059.1-2012对测定过程中引入的标准不确定度分量进行了评定。结果表明:影响氧化诱导期测定结果的最主要因素是测量重复性和恒温温度,氧气流量和样品质量对测定结果的影响较小;利用差示扫描量热法测定的该聚乙烯氧化诱导期的扩展不确定度U=1.5min(包含因子k=2)。

Taking a black polyethylene particles as the research object,according to GB/T 19466.6-2009,the oxidation induction time（OIT）of the sample at a constant temperature of 220 ℃ was measured,and the influence of the sample mass,constant temperature,oxygen flow rate and other parameters on the measurement result was discussed.And then the standard uncertainty components introduced during the measurement were evaluated according to JJF 1059.1-2012.The results show that the most important factors affecting the OIT measurement results were measurement repeatability and constant temperature,and oxygen flow and sample mass had little effect on the measurement results.The expanded uncertainty of OIT of the polyethylene measured by differential scanning calorimetry method was as following：U=1.5 min when the coverage factor k=2.