High-density polyethylene/zinc oxide nanocomposite with antibacterial and anti-UV radiation properties to reduce evaporation from free surface waters

Climate change, through rising temperatures, higher evaporation rates, and changes in rainfall, can significantly affect the availability of water resources. Evaporation losses from open-air reservoirs can exacerbate the problem of water scarcity, making it difficult to conserve water. Accordingly, this research aimed to develop nano-reinforced floating covers to reduce evaporation from free water surfaces. For this purpose, high-density polyethylene (HDPE), and zinc oxide (ZnO) nanoparticles, via melt-blending procedures, were used to fabricate the nanocomposites. The morphological, mechanical, antibacterial, and photo-degradation responses of HDPE/ZnO nanocomposites were assessed, and the physicochemical parameters of water samples were also examined to ensure that nanocomposites did not negatively affect water quality. The results indicated that adding 1 wt% nanofiller increased the tensile strength, while flexural strength values were modestly improved by increasing nanofillers up to 10 wt%. The irradiated nanocomposites generally displayed significant enhancement not only in the tensile strength but also in the flexural strength. Meanwhile, the addition of ZnO to HDPE had no adverse effects on water quality, though contributing to the antibacterial performance of the specimens over the neat polymer. To conclude, the fabricated nanocomposite with 1 wt% ZnO could be proposed as a promising candidate to reduce evaporation losses from free water surfaces, especially in arid and semi-arid areas.

Automated summary

The study aimed to reduce water surface evaporation by developing nano-reinforced floating covers, with results showing that adding 1% nanofillers can improve the tensile strength of HDPE/ZnO nanocomposites without negatively affecting water quality. The fabricated nanocomposite with 1% ZnO is considered a promising candidate for reducing water surface evaporation losses.