Artificial ageing of polymeric insulation jackets is routinely performed in order to assess end‐of‐life material characteristics. Practical constraints including high temperatures/short times ageing treatments lead to strong influence of diffusion‐limited oxidation (DLO) resulting in unreliable life‐time predictions. This study proposes a new experimental approach to the investigation of cable insulation ageing, exploiting analytical techniques capable of resolving chemistry at the length scale relevant for DLO (nano‐microscale). When studying the potential effects of DLO using time of flight secondary ion mass spectrometry (ToF‐SIMS) sample preparation becomes crucial. This paper presents the development of a methodology to generate suitable specimens to investigate the DLO effect using ToF‐SIMS. A reference polymeric material has been thermally aged in various DLO conditions. Cross sections of aged samples were generated using three different methods. In order to assess the most suitable approach for this study, cross‐section topography were scanned using a profilometer and the surface chemistry was investigated using ToF‐SIMS together with multivariate analysis methods.

中文翻译：

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通过ToF-SIMS研究热老化交联聚乙烯的异质氧化的方法

为了评估报废材料的特性，通常会对聚合物绝缘外套进行人工老化。包括高温/短时老化处理在内的实际限制条件会导致扩散限制氧化（DLO）的强烈影响，从而导致寿命预测不可靠。这项研究提出了一种新的实验方法，以研究电缆绝缘老化的方法，该方法采用了能够以与DLO（纳米级）相关的长度尺度解析化学的分析技术。当使用飞行时间二次离子质谱（ToF-SIMS）研究DLO的潜在影响时，样品制备变得至关重要。本文介绍了使用ToF-SIMS生成合适样本以研究DLO效应的方法的发展。参考聚合物材料已在各种DLO条件下进行了热老化。使用三种不同的方法生成老化样品的横截面。为了评估最适合本研究的方法，使用轮廓仪对横截面形貌进行了扫描，并使用ToF-SIMS和多变量分析方法对表面化学进行了研究。