Investigation of the effect of dual-size coatings on the hydrophobicity of cotton surface
A series of silica nanoparticles with two different length scales were introduced onto the cotton substrates to study the correlation between the surface structure and observed hydrophobicity. SiO2 nanoparticles of 7, 12, 20, and 40 nm in size were individually functionalized using 3-aminopropyl triethoxysilane or 3-glycidoxypropyltrimethoxysilane. Amino functionalized silica nanoparticles were durably attached to the cotton surface that was previously treated with epichlorohydrin. By depositing an additional layer of epoxy modified silica nanoparticles, a dual-size hierarchical coating was obtained. It was found that the order of deposition of particles to develop dual-size coatings determines the surface roughness, hydrophobicity and the amount of silica loaded on the cotton substrate. Deposition of the bigger nanoparticles on top of smaller ones resulted in rougher surfaces, higher hydrophobicity and higher amount of silica loading onto the cotton surface. A strong correlation between the size ratio of deposited nanoparticle combinations and the amount of silica loading was observed. It was found that there is also a direct relationship between the surface roughness and the hydrophobicity of the samples generated. Based upon these correlations, it is now possible to tune surface roughness and subsequent wettability by controlling the sizes of the dual-type nanoparticle layers.
KeywordsSiO2 Nanoparticles Hydrophobicity Texturing Hierarchical surface coating
We would like to thank The University of Tulsa Department of Chemistry & Biochemistry for its support. We greatly appreciate the financial support from The University of Tulsa Institute of Nanotechnology and Faculty Development Summer Fellowship. We are grateful to Mrs. Edie Cottrell for her help in the preparation of this manuscript. We would like to thank Ms. Paige Johnson for her help in SEM and EDX analyses.
- Ramaratnam K, Iyer S, Kinnan M, Chumanov G, Brown P, Luzinov I (2008) Ultrahydrophobic textiles using nanoparticles: lotus approach. JEFF 3:1–14Google Scholar
- Xue CH, Jia ST, Zhang J, Tian LQ, Chen HZ, Wang M (2008) Preparation of superhydrophobic surfaces on cotton textiles. Sci Tech Adv Mater 9:1–8Google Scholar