Lavoie Fernando Luiz, Kobelnik Marcelo, Valentin Clever Aparecido, Tirelli Érica Fernanda da Silva, Lopes Maria de Lurdes, Silva Jefferson Lins da
Department of Civil Engineering, Mauá Institute of Technology, São Caetano do Sul 09580-900, Brazil.
São Carlos School of Engineering, University of São Paulo-USP, São Paulo 13566-590, Brazil.
Membranes (Basel). 2021 May 26;11(6):390. doi: 10.3390/membranes11060390.
High-density polyethylene (HDPE) geomembranes are polymeric geosynthetic materials usually applied as a liner in environmental facilities due to their good mechanical properties, good welding conditions, and excellent chemical resistance. A geomembrane's field performance is affected by different conditions and exposures, including ultraviolet radiation, thermal and oxidative exposure, and chemical contact. This article presents an experimental study with a 1.0 mm-thick HDPE virgin geomembrane exposed by the Xenon arc weatherometer for 2160 h and the ultraviolet fluorescent weatherometer for 8760 h to understand the geomembrane's behavior under ultraviolet exposure. The evaluation was performed using the melt flow index (MFI) test, oxidative-induction time (OIT) tests, tensile test, differential scanning calorimetry (DSC) analysis, and Fourier transform infrared spectroscopy (FTIR) analysis. The sample exposed in the Xenon arc equipment showed a tendency to increase the MFI values during the exposure time. This upward trend may indicate morphological changes in the polymer. The tensile behavior analysis showed a tendency of the sample to lose ductility, without showing brittle behavior. The samples' OIT test results under both device exposures showed faster antioxidant depletion for the standard OIT test than the high-pressure OIT test. The DSC and FTIR analyses did not demonstrate the polymer's changes.
高密度聚乙烯（HDPE）土工膜是一种聚合土工合成材料，由于其良好的机械性能、良好的焊接条件和出色的耐化学性，通常用作环境设施中的衬垫。土工膜的现场性能受不同条件和暴露因素的影响，包括紫外线辐射、热暴露和氧化暴露以及化学接触。本文进行了一项实验研究，将1.0毫米厚的HDPE原生土工膜在氙弧老化试验箱中暴露2160小时，并在紫外线荧光老化试验箱中暴露8760小时，以了解土工膜在紫外线暴露下的性能。使用熔体流动指数（MFI）测试、氧化诱导时间（OIT）测试、拉伸测试、差示扫描量热法（DSC）分析和傅里叶变换红外光谱（FTIR）分析进行评估。在氙弧设备中暴露的样品在暴露期间显示出MFI值增加的趋势。这种上升趋势可能表明聚合物的形态发生了变化。拉伸性能分析表明样品有失去延展性的趋势，但未表现出脆性。在两种设备暴露下样品的OIT测试结果表明，标准OIT测试的抗氧化剂消耗比高压OIT测试更快。DSC和FTIR分析未证明聚合物发生变化。
