Facile method for the preparation of superhydrophobic cellulosic paper

• Published in: Applied surface science 2019-12, Vol.496, p.143648, Article 143648
• Main Authors: Musikavanhu, Brian, Hu, Zhijun, Dzapata, Ratidzo Lisah, Xu, Yinchao, Christie, Peter, Guo, Daliang, Li, Jing
• Format: Article
• Language: English
• Subjects: Cellulosic paper; Crystalline structure; Nanoparticles; Superhydrophobic surface
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2019.143648

We presented a three-step method for the preparation of superhydrophobic cellulose filter paper. It involved ZnCl2 pre-treatment to activate the cellulose fibers, a SiO2 sol-gel process to increase surface roughness and grafting of hexadecyl trimethoxysilane groups to chemically enhance the water repellency. The water contact angle of the modified paper reached 154.8°. XRD analysis confirmed silica as the product from the sol-gel process. EDS and SEM analysis showed that pre-treatment results in greater silica adhesion and retention on the paper surface. The modified paper proved to be self-cleaning and resistant to staining. Further tests under various conditions showed that ZnCl2 pre-treatment improved the durability of the superhydrophobic paper. It was concluded that pre-treatment of the filter paper prior to superhydrophobic coating results in a disruption in the cellulose crystalline structure that favours greater silica adhesion and retention. [Display omitted] •ZnCl2 pre-treatment exposed more -OH groups.•ZnCl2-pre-treatment and silica functionalization resulted in strong hydrogen bonding.•ZnCl2-pre-treated paper retained more silica.•Operational in various solvent and pH conditions•The paper proved to be self-cleaning, anti-staining and oleophobic.