Transforming hydrophobicity of high-density polyethylene surface to hydrophilicity and superoleophobicity by surface grafted with polyvinyl alcohols for oil contaminants cleanup

High-density Polyethylene (HDPE) is widely used in industrial processes due to its excellent mechanical properties, solvent resistance and chemical stability. However, its surface usually shows high hydrophobicity and lipophilicity, which makes it ineffective in resisting contamination by oil pollution. In this study, Polyvinyl alcohols (PVA) were grafted onto the surface of the glycidyl methacrylate (GMA) grafted HDPE to improve the surface hydrophilization, furthermore, the surface structure of the PVA@GMA-HDPE and the factors affecting its hydrophilic modification were investigated. The introduction of the GMA in HDPE surface results in a large number of reactive sites on the inert surface of HDPE, which allows for further grafting of PVA onto the HDPE surface. Most importantly, the addition of PVA improves the water wettability, which reduced the water contact angle from 87.82° to 23.33° in the air and increased the oil contact angle from 107.30° to 156.90° under water. With the help of the significant improvements in resistance to oil contamination, the grease on the surface of the modified HDPE can be easily removed by washing with water after many repetitions. The low cost, simple manufacture and versatility of the PVA@GMA-HDPE with superior hydrophilicity and submerged superoleophobicity have significant application value for sewerage pipes and membranes. [Display omitted] •Hydrophilic modified of high-density polyethylene (HDPE) by polyvinyl alcohol (PVA).•The optimal reaction time for PVA modified HDPE is 2 h.•The water contact angle (WCA) of PVA@GMA-HDPE sheet reached 23.33°.•The oil contact angle (OCA) of PVA@GMA-HDPE sheet reached 156.9° under water.•The PVA@GMA-HDPE sheet has superior resistance to oil adhesion.