scholarly journals An Experimental Investigation of ZnO Nanoparticles Effect on the Acrylic Coatings

2019 ◽  
Vol 35 (1) ◽  
pp. 216-220
Author(s):  
Ghazaleh Khalaji ◽  
Mostafa Maleki ◽  
Ashkan `Memand

In this study, the properties of acrylic coatings based on paraloid B-72 were improved by adding of ZnO nanoparticles. Steel plates were used as substrate. ZnO nanoparticles was analyzed by transmission electron microscopy (TEM). The effect of adding ZnO nanoparticles on the the coatings was investigated using contact angle measurements. The modified coating with a ZnO nanoparticles showed more efficient performance than the net coating after 30 days UV radiation. Generally, this work confirm the positive effect of adding ZnO nanoparticles on acrylic coatings.

2016 ◽  
Vol 22 (S3) ◽  
pp. 1610-1611
Author(s):  
Jonathan E. Cowen ◽  
Ashley E. Harris ◽  
Cecelia C. Pena ◽  
Stephen C. Bryant ◽  
Allison J. Christy ◽  
...  

Clay Minerals ◽  
2018 ◽  
Vol 53 (4) ◽  
pp. 643-656 ◽  
Author(s):  
Zhi-Lin Cheng ◽  
Xing-Yu Chang ◽  
Zan Liu ◽  
Dun-Zhong Qin

ABSTRACTIn order to improve the dispersibility of halloysite nanotubes (HNTs) in polytetrafluoroethylene (PTFE), the modification of HNT surfaces was studied with three types of modifiers (polymethyl methacrylate [PMMA], sodium dodecyl sulfate [SDS] and carboxylic acid). The modified HNTs were characterized by Fourier-transform infrared (FTIR) spectrometry, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and contact angle measurements. The HNTs were used to reinforce the mechanical properties of PTFE. The mechanical results indicated that the tensile strength of the modified HNT-filled PTFE nanocomposites (F-HNT/PTFE) improved to an acceptable degree and Young's modulus increased significantly. The tribological results showed that the wear rate of F-HNT/PTFE decreased by 21–82 and 9–40 times compared to pure PTFE and the pristine F-HNT/PTFE, respectively.


2019 ◽  
Vol 13 (2) ◽  
pp. 151-159
Author(s):  
Blanca I.M. Mejia ◽  
Oxana V. Kharissova ◽  
Boris I. Kharisov

Background: The addition of nanoparticles to cellulose paper can improve its mechanical strength, chemical stability, biocompatibility and hydrophobic properties. Silica nanoparticles are known to be inert, hydrophobic, biocompatible, biodegradable and have a good distribution in being deposited on surfaces. The main characteristics of 20 nm SiO2 nanoparticles are good chemical and thermal stability with a melting point of 1610-1728°3C, a boiling point of 2230°C with a purity of 99.5%. Objective: To carry out the hydrophobization of paper based on Kraft cellulose and on cellulose obtained from soybean husk with 20-nm size SiO2 nanoparticles and to study hydrophobicity, morphology and topography of the prepared composites. Methods: The ground and roasted soybean husk was treated with a NaOH, washed and dried. Hydrophobization of paper was carried in aqueous medium by SiO2 addition in weight ratios “paper-SiO2” of 0.01-0.05 wt.%, stirring, filtration and drying. The obtained cellulose sheet composites were characterized by Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), FTIRspectroscopy, Mullen proofs of hydrophobicity, and contact angle measurements. Results: The mechanical properties of paper nanocomposites (tensile strength and compression) increased considerably by varying the concentrations. The tensile strength increased by 41-46% and the compressive strength increased by 55-56%. The existence of fiber nanofoils, good adhesion of 20-nm SiO2 nanoparticles to the paper surface, and their homogeneous distribution were observed. Conclusion: Cellulose was successfully obtained from soybean husk, applying the alkaline-based extraction method. A good reinforcement of cellulose fibers is observed due to the outstanding characteristics of the silicon dioxide nanoparticles.


2007 ◽  
Vol 561-565 ◽  
pp. 1255-1258
Author(s):  
D.Y. Han ◽  
C.B. Shen ◽  
Wei Wei Shi ◽  
D.D. Li ◽  
Zu Bin Chao ◽  
...  

ZnO nanoparticles were carried out by Microemulsion method in the presence of TritonX-100 (poly oxyethylene tert-octylphenyl ether) as a surfactant. X-100/n-hextnol/cyclohexane/ waterW/O microemulsion system was also determined. Zinc chloride (ZnCl2·2H2O) and ammonia (NH3·H2O) were used as raw materials. The results indicated that the formation of ZnO nanoparticles was confirmed, using X-ray diffractometer (XRD) and transmission electron microscopy (TEM). The results showed that the nanoparticle was exactly ZnO with wurtzite type crystalline structure and the size of nanoparticles is strongly affected by the ratio of water to surfactant(R). With the R value increase, the particles size became larger.


2020 ◽  
Vol 93 (2) ◽  
pp. 286-296
Author(s):  
N. T. Thuong ◽  
N. P. D. Linh ◽  
C. H. Ha ◽  
P. T. Nghia ◽  
S. Kawahara

ABSTRACT NR/Na+-montmorillonite (NR/Na+-MMT) nanocomposites were prepared through mixing in the latex stage. NR/Na+-MMT nanocomposites with various amounts of Na+-MMT were fabricated using three types of NR latexes: fresh NR (FNR), high ammonia NR, and deproteinized NR latex. The Na+-MMT and NR latexes were characterized by particle size distribution and Fourier transform infrared spectroscopy analyses. The nanocomposite materials were then analyzed by scanning electron microscopy, transmission electron microscopy, and contact angle measurements. The mechanical properties of the resulting products were measured by tensile testing machine. The composite prepared from FNR gave the best tensile strength at 3 phr MMT loading. The outstanding properties are proposed to be due to the contribution of the water-soluble compounds present in FNR that possess similar hydrophilicity to Na+-MMT.


2004 ◽  
Vol 449-452 ◽  
pp. 1133-1136 ◽  
Author(s):  
Dong Un Seo ◽  
Cheng Zhu Lu ◽  
Ho Jung Chang ◽  
Sang Woo Joo

We examined quenching of growth of ZnO nanoparticles with the injection of various organic surfactants. Aliphatic isocyanides as well as organothiols were found to adsorb on ZnO nanoparticle surfaces. For a carboxylate-terminated thiol, a retardation of growth appeared to be effective presumably due to the adsorption of the carboxylate COO- group on the ZnO surface. Photoluminescence spectra and transmission electron microscopy images were obtained for thiolcapped ZnO nanoparticles. The thiol-capped ZnO nanoparticles was found to fluoresce at the wavelength shorter by ~6 nm than those in the absence of any organic surfactants.


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):  
R. W. Anderson ◽  
D. L. Senecal

A problem was presented to observe the packing densities of deposits of sub-micron corrosion product particles. The deposits were 5-100 mils thick and had formed on the inside surfaces of 3/8 inch diameter Zircaloy-2 heat exchanger tubes. The particles were iron oxides deposited from flowing water and consequently were only weakly bonded. Particular care was required during handling to preserve the original formations of the deposits. The specimen preparation method described below allowed direct observation of cross sections of the deposit layers by transmission electron microscopy.The specimens were short sections of the tubes (about 3 inches long) that were carefully cut from the systems. The insides of the tube sections were first coated with a thin layer of a fluid epoxy resin by dipping. This coating served to impregnate the deposit layer as well as to protect the layer if subsequent handling were required.


Author(s):  
S. Fujishiro

The mechanical properties of three titanium alloys (Ti-7Mo-3Al, Ti-7Mo- 3Cu and Ti-7Mo-3Ta) were evaluated as function of: 1) Solutionizing in the beta field and aging, 2) Thermal Mechanical Processing in the beta field and aging, 3) Solutionizing in the alpha + beta field and aging. The samples were isothermally aged in the temperature range 300° to 700*C for 4 to 24 hours, followed by a water quench. Transmission electron microscopy and X-ray method were used to identify the phase formed. All three alloys solutionized at 1050°C (beta field) transformed to martensitic alpha (alpha prime) upon being water quenched. Despite this heavily strained alpha prime, which is characterized by microtwins the tensile strength of the as-quenched alloys is relatively low and the elongation is as high as 30%.


Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).


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