Dear Colleagues and Students,
You are cordially invited to UNAM Nanocolloquium seminars focusing on advancements in the field of nanoscience and nanotechnology. The seminars bring us the most recent developments in these exciting fields.
The third talk of this fall term will be presented by Prof. İskender Yılgör*
Title: Superhydrophobic polymer surfaces: Effect of surface micro/nanostructure
Date: November 18, 2016 (Friday)
Place: UNAM Conference Room
ABSTRACT – Effect of the coating method and surface micro/nanostructure on the formation of superhydrophobic polymer surfaces, modified by the incorporation of hydrophobic fumed silica nanoparticles were investigated. Four different silica/polymer dispersions, which included polydimethylsiloxane-urea (PSU), poly(methyl methacrylate) (PMMA), polystyrene (PS) and epoxy resin (ER) were coated onto glass substrates using; (i) layer-by-layer spin-coating, (ii) spray coating by an air-brush, and (iii) doctor blade coating. Influence of the coating method, composition of the polymer/silica mixtures and the number of silica layers applied on the topography and wetting behavior of the surfaces were determined. Surfaces obtained were characterized by scanning electron microscopy (SEM), atomic force microscopy (AFM), white light interferometry (WLI) and advancing and receding water contact angle measurements. It was demonstrated that surfaces with dual micro/nano roughness, that display superhydrophobic behavior could be obtained by all methods. Applicability of Wenzel and Cassie-Baxter models to the experimentally determined static water contact angles on three polymer surfaces with different chemical structures (PSU, PMMA and PS) was investigated. Various commercial applications of these superhydrophobic surfaces currently underway will also be discussed.
* Koç University, Department of Chemistry
All interested are cordially invited!