Abstract：The hydrophobic conversion of hydrophilic polyethylene terephthalate (PET) and polyvinyl chloride (PVC) plastics in different environments was researched on the basis of surface reconstruction and thermodynamics, aiming at the floatability fluctuation of waste plastics. It was revealed that 82%, 47% and 0.2% of PET hydrophobicity was recovered in air, ethanol, and water at temperature 70℃, and 100%, 37%, and 2% of PVC hydrophobicity was recovered. A non-polar air environment with high temperature favoured surface reconstruction and hydrophobicity restoration, while a polar water environment with low temperature induced hydrophilic plastic surfaces. Compared with the surface coating, the surface alcoholysis was more conducive to maintaining the hydrophilicity of the plastic. This study proposed that changing the molecules structure of plastic surface was beneficial to maintaining their hydrophilicity, and a low-temperature-entire-immersion process assisted plastic flotation in stability.
张迎霜, 杨雅斌, 蒋鸿儒, 王晖. 环境诱导表面重构调控PVC和PET塑料的可浮性[J]. 中国环境科学, 2022, 42(2): 761-769.
ZHANG Ying-shuang, YANG Ya-bin, JIANG Hong-ru, WANG Hui. Regulating PVC and PET floatability based on surface reconstruction induced by environments. CHINA ENVIRONMENTAL SCIENCECE, 2022, 42(2): 761-769.
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