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A slippery oil-repellent hydrogel coating

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Jingwei Lu
Jingwei Lu
Jingwei Lu
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Zhu Xiaotao at Hohai University
Zhu Xiaotao
Bo Wang at yangzijiang
Bo Wang
  • yangzijiang
Li Liu
Li Liu
Li Liu
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Abstract and Figures

Development of oil-repellent coatings that are anti-fouling with water alone is highly desirable, yet still challenging. Herein, to address this challenge, we fabricate a slippery oil-repellent hydrogel coating that exhibits oil repellency when exposed in the air as well as underwater. In the air, water wets the slippery oil-repellent hydrogel coating surface completely, while organic liquid drops such as toluene can slide off the water wetted coating surface easily. When immersed in water, the slippery oil-repellent hydrogel coating surface exhibits excellent underwater superoleophobic property with all oil contact angles more than 159° and oil adhesive forces less than 1 μN. The hydrogel coating keeps its oil repellency after long-term outdoor storage, thermal treatment, knife scratching and other treatments. Exploiting its water-attracting and oil-repelling property, the slippery oil-repellent hydrogel coated copper mesh and filter paper are demonstrated as reusable membranes to separate oil–water mixtures with separation efficiency more than 97%. Graphic abstract
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ORIGINAL RESEARCH
A slippery oil-repellent hydrogel coating
Jingwei Lu .Xiaotao Zhu .Bo Wang .Li Liu .Yuanming Song .
Xiao Miao .Guina Ren .Xiangming Li
Received: 4 September 2019 / Accepted: 19 December 2019 / Published online: 1 January 2020
ÓSpringer Nature B.V. 2020
Abstract Development of oil-repellent coatings that
are anti-fouling with water alone is highly desirable,
yet still challenging. Herein, to address this challenge,
we fabricate a slippery oil-repellent hydrogel coating
that exhibits oil repellency when exposed in the air as
well as underwater. In the air, water wets the slippery
oil-repellent hydrogel coating surface completely,
while organic liquid drops such as toluene can slide
off the water wetted coating surface easily. When
immersed in water, the slippery oil-repellent hydrogel
coating surface exhibits excellent underwater super-
oleophobic property with all oil contact angles more
than 159°and oil adhesive forces less than 1 lN. The
hydrogel coating keeps its oil repellency after long-
term outdoor storage, thermal treatment, knife scratch-
ing and other treatments. Exploiting its water-attract-
ing and oil-repelling property, the slippery oil-
repellent hydrogel coated copper mesh and filter paper
are demonstrated as reusable membranes to separate
oil–water mixtures with separation efficiency more
than 97%.
Electronic supplementary material The online version of
this article (https://doi.org/10.1007/s10570-019-02953-5) con-
tains supplementary material, which is available to authorized
users.
J. Lu X. Zhu (&)B. Wang L. Liu
Y. Song G. Ren (&)X. Li
School of Environmental and Material Engineering,
Yantai University, Yantai 264405, China
e-mail: xiaotao.zhu@ytu.edu.cn
G. Ren
e-mail: rgnlicp@126.com
X. Miao
Shandong Key Laboratory of Optical Communication
Science and Technology, School of Physics Science and
Information Technology, Liaocheng University,
Liaocheng 252000, China
123
Cellulose (2020) 27:2817–2827
https://doi.org/10.1007/s10570-019-02953-5(0123456789().,-volV)(0123456789().,-volV)
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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