Fabrication of ZnO nanoarchitectured fluorine-free robust superhydrophobic and UV shielding polyester fabrics for umbrella canopies

U G Mihiri Ekanayake; N Rathuwadu; M M M G P G Mantilaka; R M G Rajapakse

doi:10.1039/c8ra06373g

Fabrication of ZnO nanoarchitectured fluorine-free robust superhydrophobic and UV shielding polyester fabrics for umbrella canopies

RSC Adv. 2018 Sep 6;8(55):31406-31413. doi: 10.1039/c8ra06373g. eCollection 2018 Sep 5.

Authors

U G Mihiri Ekanayake^{1

2}, N Rathuwadu³, M M M G P G Mantilaka^{2

3}, R M G Rajapakse^{2

4}

Affiliations

¹ Academy of Sri Lanka Institute of Nanotechnology (SLINTEC Academy) Nanotechnology and Science Park, Mahenwatte, Pitipana, Homagama Sri Lanka.
² Postgraduate Institute of Science (PGIS), University of Peradeniya Peradeniya Sri Lanka.
³ Sri Lanka Institute of Nanotechnology (SLINTEC) Nanotechnology and Science Park, Mahenwatte, Pitipana, Homagama Sri Lanka prasangam@slintec.lk mantilaka@gmail.com +94 114650532 +94 114650556 +94 719398233.
⁴ Department of Chemistry, Faculty of Science, University of Peradeniya Peradeniya Sri Lanka.

Abstract

Mechanically robust, durable, fluorine-free superhydrophobic and UV shielding surfaces are fabricated on polyester umbrella canopy fabrics by self-assembly of stearic acid on zinc oxide (ZnO) nanoarchitectures on polyester fabrics. Drawbacks of conventional umbrella canopies including rain water penetration through the canopy during heavy rains, wet canopies taking too long to dry, and limited blockage of harmful UV radiation have been overcome with the surface modified canopy fabrics in the present study. Herein, in the typical synthesis, the polyester fabric is dipped in Zn(NO₃)₂ : hexamethylenetetraamine (HMT), at 1 : 1 molar ratio solution and heated at 100 °C for 2 h to grow ZnO nanoarchitectures on the fabric surface. Stearic acid is allowed to self-assemble by dipping the fabric in 1 g dm^-3 stearic acid solution. The modified fabrics are characterized using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis and X-ray fluorescence spectroscopic techniques. The modified fabrics show superhydrophobicity characterized by water contact angles over 150° with the optimum analyzed conditions. The superhydrophobic layer formed on the fabric is resistant to acid rain and stayed durable throughout 50 abrasion cycles and under 1.5 h strong surfactant washing. The developed method is useful to fabricate a smart umbrella canopy with acid rain resistant, durable, robust superhydrophobic and UV blocking properties.