Development of surface modified PU foam with improved oil absorption and reusability via an environmentally friendly and rapid pathway. Issue 1 (February 2022)

• Record Type: Journal Article
• Authors: Seah, Mei Qun; Ng, Zhi Chien; Lau, Woei Jye; Gürsoy, Mehmet; Karaman, Mustafa; Wong, Tuck-Whye; Ismail, Ahmad Fauzi
• Is Part Of: Journal of environmental chemical engineering. Volume 10:Issue 1(2022)
• Publication Date: 2022-02
• Subjects: Oil absorption -- PU foam -- Green approach -- Hydrophobic -- Plasma; Chemical engineering -- Environmental aspects -- Periodicals; Environmental engineering -- Periodicals; Chemical engineering -- Environmental aspects; Environmental engineering; Periodicals; 660.0286
• DOI: 10.1016/j.jece.2021.106817
• Languages: English
• ISSNs: 2213-2929

Abstract

Abstract: Although the commercial polyurethane (PU) foams are hydrophobic in nature, they generally show low degree of reusability for oil and organic solvent absorption. In this work, we proposed a solvent-free and rapid surface functionalization approach based on chemical vapor deposition (CVD) process to improve the surface characteristics of PU foam, increasing not only its reusability but also its absorption capacity. Among the monomers used to functionalize the surface of foam, our results showed that only hexamethyldisiloxane (HMDSO) and 2, 2, 3, 4, 4, 4-hexafluorobutyl acrylate (HFBA) were promising to increase the absorption performance of the control PU foam, owing to the enhanced foam's surface hydrophobicity (with contact angle increased from ~106° to 120–135°) without altering the foam's porosity. These promising features are attributed to the formation of ultrathin highly hydrophobic yet uniform layer on the foam surface. Further investigation indicated that the modified foams outperformed the control foam for the multicycle cyclohexane and crude oil absorption (up to 10 cycles) by showing significantly higher absorption capacity. The reusability of the modified foams could be further improved when ethanol was employed to rinse the saturated foam after each absorption cycle. Such solvent rinsing help in maintaining the foam absorption capacity. In conclusion, the proposed greener surface modification method clearly demonstrated its effectiveness in functionalizing the PU foam, leading to higher absorption capacity against cyclohexane and crude oil as well as higher degree of reusability. Graphical Abstract: ga1 Highlights: A solvent-free and rapid approach to improve surface characteristics of PU foam. CVD-functionalized PU is able to overcome drawbacks of commercial PU. Functionalized PU showed promising cyclohexane and crude oil absorption. Functionalization prevents PU structure from damage even after ethanol washing.