Comb-like poly(dodecyl methacrylate) modified SiO2 nanoparticles as nanohybrid coatings: Electron beam grafting and tuning superhydrophobic/water-repellent surface studies

2022 ◽  
Vol 163 ◽  
pp. 106658
Author(s):  
Eakkapap Huajaikaew ◽  
Thananchai Piroonpan ◽  
Kasidit Booncharoen ◽  
Wanvimol Pasanphan
2020 ◽  
Vol 71 (04) ◽  
pp. 297-301
Author(s):  
LAURA CHIRILA ◽  
LUDMILA OTILIA CINTEZA ◽  
MARIA TANASE ◽  
DIANA ELENA RADULESCU ◽  
DENISA MARIA RADULESCU ◽  
...  

This study presents a strategy to obtain textile materials with hydrophobic/oleophobic effect by applying hybrid coatings based on a mixture of flower-like ZnO nanoparticles and organically modified SiO2 nanoparticles (ORMOSIL). The obtained dispersions based on both types of nanoparticles are stable, with unimodal distribution of smaller quasi spherical shape and average size of 158 nm for SiO2 nanoparticles and respectively, with bimodal distribution with a broad distribution of particle size and average size of 144 nm and 435 nm for ZnO flower-like nanoparticles. The ZnO/SiO2 NPs based dispersions were then applied on 100% cotton fabrics on a laboratory scale by padding method in two successive phases. The functionalized cotton fabrics were evaluated in terms of surface morphology changes, whiteness degree and water and oils repellent properties. The developed textile materials exhibited a low wetting capacity, with high values of water absorption time (>15 minutes) and a water-repellent degree of 75 (AATCC photographic scale) and 2.5 respectively (ISO scale) showing an acceptable hydrophobic effect. The functionalization treatment based on mixture of ZnO/SiO2 nanoparticles led to obtaining an efficient cotton substrate for the rejection and protection against the oily substances which exhibit an oil repellency degree of 6. Also, the functionalization treatments did not significantly change the surface morphology of the fibres, suggesting that the bulk properties of the cotton fibres remained undamaged.


2016 ◽  
Vol 17 (7) ◽  
pp. 1013-1017 ◽  
Author(s):  
Zhiming Jiang ◽  
Yahui Wang ◽  
Yin Liu ◽  
Xuehong Ren

Coatings ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 334 ◽  
Author(s):  
Aikaterini Chatzigrigoriou ◽  
Ioannis Karapanagiotis ◽  
Ioannis Poulios

Calcium hydroxide (Ca(OH2)) nanoparticles are produced following an easy, ion exchange process. The produced nanoparticles are characterized using transmission electron microscopy (TEM) and Fourier- transform infrared spectroscopy (FTIR) and are then dispersed in an aqueous emulsion of silanes/siloxanes. The dispersions are sprayed on marble and the surface structures of the deposited coatings are revealed using scanning electron microscopy (SEM). By adjusting the nanoparticle concentration, the coated marble obtains superhydrophobic and water repellent properties, as evidenced by the high static contact angles of water drops (> 150°) and the low sliding angles (< 10°). Because Ca(OH)2 is chemically compatible with limestone-like rocks, which are the most common stones found in buildings and objects of the cultural heritage, the produced composite coatings have the potential to be used for conservation purposes. For comparison, the wetting properties of another superhydrophobic and water repellent coating composed of the same siloxane material and silica (SiO2) nanoparticles, which were commonly used in several previously published reports, were investigated. The suggested siloxane+Ca(OH)2 composite coating offers good protection against water penetration by capillarity and has a small effect on the aesthetic appearance of marble, according to colorimetric measurements.


RSC Advances ◽  
2018 ◽  
Vol 8 (48) ◽  
pp. 27064-27072 ◽  
Author(s):  
Frances L. Heale ◽  
Kristopher Page ◽  
James S. Wixey ◽  
Philip Taylor ◽  
Ivan P. Parkin ◽  
...  

Special wettability durable coatings, with water contact angles exceeding 140°, have been fabricated using inexpensive and non-toxic functionalised hydrophobic-silica nanoparticles embedded in fatty acids.


2021 ◽  
Vol 22 (10) ◽  
pp. 447-457
Author(s):  
N. P. Prorokova ◽  
◽  
T. Yu. Kumeeva ◽  
I. V. Kholodkov ◽  
V. M. Bouznik ◽  
...  

The control possibility assessment of the water-repellent properties of polyester (PEF) fabric when its hydrophobizing with tetrafluoroethylene (TFE) telomers due to texturing by applying nanosized SiO2 is discussed. It was established that the use of a compound containing SiO2 nanoparticles and TFE telomers for hydrophobization of PEF fabrics led to an increase in roughness of the coatings, however, a decrease in contact angles of fabric and an increase in its water absorption were observed. This is due to an additional increase in hardness of the coating based on TFE telomers, when combined with SiO2 nanoparticles.


2012 ◽  
Vol 12 (6) ◽  
pp. 1467-1471 ◽  
Author(s):  
Jin Hyoung Kim ◽  
Youngku Sohn ◽  
Insoo Kim ◽  
Bumsoo Han ◽  
Weon Gyu Shin

Author(s):  
G. G. Shaw

The morphology and composition of the fiber-matrix interface can best be studied by transmission electron microscopy and electron diffraction. For some composites satisfactory samples can be prepared by electropolishing. For others such as aluminum alloy-boron composites ion erosion is necessary.When one wishes to examine a specimen with the electron beam perpendicular to the fiber, preparation is as follows: A 1/8 in. disk is cut from the sample with a cylindrical tool by spark machining. Thin slices, 5 mils thick, containing one row of fibers, are then, spark-machined from the disk. After spark machining, the slice is carefully polished with diamond paste until the row of fibers is exposed on each side, as shown in Figure 1.In the case where examination is desired with the electron beam parallel to the fiber, preparation is as follows: Experimental composites are usually 50 mils or less in thickness so an auxiliary holder is necessary during ion milling and for easy transfer to the electron microscope. This holder is pure aluminum sheet, 3 mils thick.


Author(s):  
Kenneth H. Downing ◽  
Robert M. Glaeser

The structural damage of molecules irradiated by electrons is generally considered to occur in two steps. The direct result of inelastic scattering events is the disruption of covalent bonds. Following changes in bond structure, movement of the constituent atoms produces permanent distortions of the molecules. Since at least the second step should show a strong temperature dependence, it was to be expected that cooling a specimen should extend its lifetime in the electron beam. This result has been found in a large number of experiments, but the degree to which cooling the specimen enhances its resistance to radiation damage has been found to vary widely with specimen types.


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