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Basalt fabric with manufacturer-made silane sizing was additionally treated by propane-butane enriched atmospheric pressure nitrogen plasma for 15 and 30 s. The wetting improvement of treated fabric was demonstrated by faster soaking of K2CO3 solution. FTIR and XPS analyses confirmed the presence of new nitrogen-containing chemical groups. The impact on adhesion was investigated via a shear strength test of basalt fabric inlay between two beech wooden boards. A short 15 s long treatment led to almost 50% increase in melamine-urea formaldehyde (MUF), polyvinyl acetate (PVAC) and epoxy resin bond strength. Phenol-resorcinol formaldehyde (PRF) needed longer treatment to achieve a bond strength of 11.2 MPa. Only the polyurethane (PUR) showed reduced adhesion to plasma-treated fibers. However, from all tested resins, PUR exhibited the highest bond strength (15.7 MPa) with untreated basalt fabric. The SEM of tested specimens confirmed the changes in the mechanical adherence of resins to plasma treated fibers. Based on these results, PRF and PUR seem to be the most suitable polymers for basalt fibers reinforcement of structural wood-based materials.

According to the value of water contact angle (WCA), the surfaces can be roughly defined as hydrophilic (with WCA less than 90°) or as hydrophobic (with WCA higher than 90°). Water wetting behavior plays important role and surfaces with special wettability (hydrophobic-superhydrophobic; hydrophilic-superhydrophilic) can be used both in the daily life (solar cells, smartphones, car windows, etc.) and in the industry (corrosion resistance, self-cleaning, anti-icing properties, etc.). Nowadays, the development of hydrophobic surface treatment that may be applied in the industry is very interesting topic. Therefore, it was decided to estimate the influence of radiofrequency (RF) plasma jet in atmosphere on wetting behavior of ceramic plasma sprayed coatings. As the initial material for surface treatment, yttria stabilized zirconia suspension plasma sprayed coatings were used. The influence of RF plasma jet on suspension plasma sprayed coatings was estimated on both hydrophilic and hydrophobic surfaces, and resulted water contact angle and free surface energy of modified samples were measured by sessile droplet method. Microstructure, phase composition and topography investigation were carried out by means of light microscopy, X-ray diffraction techniques and non-contact profilometry.

One-step electrolytic method for production of superhydrophobic and oil-reppelent surface on stainless steel using aqueous solution of perfluorooctanoic acid as an electrolyte compared with analogous deposition of superhydrophobic surfaces from ethanolic solutions of myristic and stearic acid. One-step electrolytic method for production of superhydrophobic and oil-reppelent surface on stainless steel using aqueous solution of perfluorooctanoic acid as an electrolyte compared with analogous deposition of superhydrophobic surfaces from ethanolic solutions of myristic and stearic acid. One-step electrolytic method for production of superhydrophobic and oil-reppelent surface on stainless steel using aqueous solution of perfluorooctanoic acid as an electrolyte compared with analogous deposition of superhydrophobic surfaces from ethanolic solutions of myristic and stearic acid. One-step electrolytic method for production of superhydrophobic and oil-repellent surface on stainless steel using aqueous solution of perfluorooctanoic acid as an electrolyte compared with analogous deposition of superhydrophobic surfaces from ethanolic solutions of myristic and stearic acid

Colonization of man-made surface materials by algae and other microorganisms, i.e. biofouling, causes various aesthetical and health problems as well as deterioration of appearance and surface functioning. The present study investigated eight complex surfaces combining various TiO2, alkoxy-siloxane and hydrophobization agents that were combined to prevent growth of phototrophic filamentous alga Klebsormidium sp. Regarding photoactivity, NOx abatement at the studied surfaces has been improved by adding anti-aggregation substances such as bentonite. Surface properties were characterized by confocal microscopy, scanning electron microscopy, SEM, with the energy dispersive X-ray spectroscopy, EDX, and the contact angle measurements. Biological experiments with Klebsormidium alga were performed in a constructed flow-through system. The results indicated that superhydrophobicity, i.e. very low surface energy, was critical for efficient antifouling during the early colonization by algae. This was specifically demonstrated in two novel composite samples made of titanium dioxide and commercial hydrophobization agent UltraEverDry. Low surface energy of these materials (around 1.3 mJ/m2), high water contact angles (>140°) as well as decent photoactivity (NOx conversions by 16.7 % and 1.4 % in UV and VIS, respectively), provide a promising basis for further longer-term anti-fouling experiments. The present study introduces novel composite materials preventing the algal fouling, and it brings new evidences on the interactive effects on hydrophobic and photoactive surfaces.