Effect of wear factors on lyophobic properties of fabric modified by a fluorosilane

Abstract

Advances in the production of textiles and items with hydro-and lipophobic and anti-adhesive properties are being made in a variety of critical directions of modern materials science with the aim of increasing the quality and competitiveness of the manufactured product. Complicated problems can be solved by using a comprehensive approach that is based on fundamental research of surface phenomena, the synthesis and preparation of new hydrophobic agents, and the improvement and development of new technical methods for finishing materials. The combined hydro-and lipophobic properties of materials are usually expressed by the term lyophobicity [1]. Lyophobicity is largely determined by the resistance of items to the action of various types of contaminants.At present, research is focused on the replication of the so-called lotus-effect, i.e., the design of superhydrophobic self-cleaning coatings that are characterized by high wetting angles and minimal angles for sliding of water drops from the surface. Such materials are being studied in dozens of scientific centers in Russia and abroad because of their unique properties (water-repellant, lipophobic, resistant to organic contaminants, etc.). Two main parameters must be considered in producing superhydrophobic properties. These are the hierarchy of surface structure including that at the nano-sized level and low critical surface tension values. The latter can be attained using various hydrophobic agents, among which functionalized fluoroorganosilicon compounds are preferred [2].It was shown earlier [3] that the use of fluorosilanes as hydrophobic agents for finishing fabrics of various composition could make them highly lipophobic. However, highly hydro-and lipophobic textiles and items based on them would be interesting to various consumers if these effects were retained during prolonged use. Herein the resistance of the lyophobic properties of modified cotton fabric to the action of various (climatic, mechanical, multiple washings, etc.) wear factors is studied.We used cotton fabric (art. 14, GOST 29298-92, madepolam) that was washed before treatment. The modifier was 2,2, 3,3,4,4,5,5,6,6,7,7,8,8,9,9,9-heptadecafluoro-N-[3-(triethoxysilyl)propyl]nonanamide (MA) of structural formulaThe compound was a yellowish oil of density 1.4324 g/cm 3 and surface tension 23.4 mJ/m 2 . Samples were treated by immersing them for 5 min in MA solution (5%) in EtOH. Then, samples were pressed to 70% moisture, dried at 130°C for 10 min, and ironed at 180 ± 2°C for 1 min. The need to perform the last step was demonstrated earlier [4,5].

Effect of the Morphology of Leather Surface on the Hydrophobic-Hydrophilic Properties

“…5% solution of 2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9,9-heptadecafluor-N-[3-triethyoxysilyl)propyl]-nonanamide (fluorine silane) in ethanol was used as a hydrophobic agent. The structural formula of this modifier is as follows, CF 3 -(CF 2 ) 7 -C(O) -NH -(CH 2 ) 3 -Si(OC 2 H 5 ) 3 High efficiency of this compound for hydrophobization of textil, leather and fur was demonstrated in paper [13,14]. The surface treatment of leather was conducted by spraying the solution perpendicular to the material surface from 20 cm above it with follow-on exposure of the specimens at temperature 20˚C -25˚C for 20 min and then for 10 min at 90˚C.…”

“…The authors of the paper [13,14] assumed that after application of fluoro-containing silane and subsequent thermal treatment of the specimens the 2-dimensional molecular layer chemically bound with the material surface is formed. The formation of the siloxane bonds (-O-Si-O-) and creation of the oligomeric layer of hydrophobizator help to change the point contacts of individual molecules into multi-centered, which improves the interactions between the formed hydrophobic layer and the leather surface.…”

Reinforced Superhydrophobic Coating on Silicone Rubber for Longstanding Anti-Icing Performance in Severe Conditions

“…On the other hand, the fluorooxysilane used in our work has three terminal functional groups, allowing it to be used as a binding agent. The reaction of one methoxy group with hydroxyl belonging to a nanoparticle located on the surface of textured silicone rubber binds a fluorooxysilane molecule to the surface, whereas the reaction of these groups with the methoxy groups of adjacent fluorooxysilane molecules leads to formation of a 2D polymer film atop the textured layer, 25 which anchors the texture elements such as nanoparticles redeposited after ablation to the silicone rubber matrix.…”

Fabrication of superhydrophobic cotton fabrics by a simple chemical modification

“…In particular, the best effect is obtained by applying fluoro derivatives of organosilicon compounds, which combine unique properties of both components (Owen and Dvornic 2012). Among this group of compounds, the most frequently applied ones were fluorofunctional trichloro-and trialkoxysilanes (Leng et al 2009;Pipatchanchai and Srikulkit 2007;Textor and Mahltig 2010;Hayn et al 2011) as well as fluorosilyl amide (Evsyukova et al 2009(Evsyukova et al , 2011Ivanova and Zaretskaya 2011). On the other hand, classical polysiloxanes were used relatively rarely because of difficulties with their adhesiveness and durability of bonding to fibers.…”