Measurement of Average Particle Size of Fine Pigments

1932 ◽  
Vol 5 (2) ◽  
pp. 202-215 ◽  
Author(s):  
S. D. Gehman ◽  
T. C. Morris
Keyword(s):  
Particle Size ◽  
Zinc Oxide ◽  
Carbon Black ◽  
Wave Length ◽  
Average Particle Size ◽  
Average Particle ◽  
Particle Sizes ◽  
Carbon Blacks ◽  
Count Method

Abstract A method of obtaining excellently dispersed suspensions of rubber pigments of accurate concentration is described in which the pigment is milled into rubber and the stock then dissolved in a solvent. The average particle sizes of carbon blacks measured by the Zsigmondy count method were found to range from 0.061μ for rubber gas black to 2.22μ for the coarsest one measured. The zinc oxide pigments had average particle sizes from 0.076μ to 0.57μ.. Measurements on several other pigments of interest are included. Because of the high visibility in the ultra-microscope, this method gives smaller values for average particle size than the photomicrographic methods. The results have been used to calibrate a microturbidimeter of the extinction type for use in measuring average particle size. Curves are included showing how the turbidities of suspensions of zinc oxide and carbon black vary with the average particle size, concentration, and wave length of light used.

Effects of Dissolving Agents on Particle Size Reduction of Titanium Dioxide Synthesized by Solution Combustion Technique

2016 ◽  
Vol 690 ◽  
pp. 236-239
Author(s):  
Oratai Jongprateep ◽  
Rachata Puranasamriddhi
Keyword(s):  
Particle Size ◽  
Titanium Dioxide ◽  
Sulfuric Acid ◽  
Nitric Acid ◽  
Average Particle Size ◽  
Average Particle ◽  
Particle Sizes ◽  
Solution Combustion ◽  
Initial Reagent ◽  
Combustion Technique

High photocatalytic activity of nanoparticulate titanium dioxide has attracted worldwide attention. Synthesis techniques of the nanoparticles, however, often require high energy supply or costly initial reagents. Solution combustion technique is an energy-effective technique capable of synthesizing nanosized titanium powders. This research aimed at utilizing a less expensive initial reagent in synthesis of nanoparticulate titanium dioxide by the solution combustion technique. The research also examined effects of dissolving agents on chemical composition and particle sizes of the synthesized powders. A low-cost initial reagent, titanium dioxide with average particle size of 154 nanometers, was dissolved in sulfuric acid or dispersed in nitric acid prior to the combustion. Experimental results revealed that the pure anatase phase titanium dioxide was successfully obtained in powders prepared from both sulfuric acid and nitric acid. The average particle size of the powder prepared from sulfuric acid was 77 nanometers, while that of the powder prepared from nitric acid was 117 nanometers. The difference in particle sizes was attributed to solubility of the initial reagent in the acid. Complete solution of initial reagent in sulfuric acid was the main factor attributed to finer particle size.

Effect of Poly(Vinyl Pyrrolidone) on Dispersing Carbon Black Particles

2013 ◽  
Vol 796 ◽  
pp. 432-436
Author(s):  
Xia Yuan
Keyword(s):  
Particle Size ◽  
Zeta Potential ◽  
Carbon Black ◽  
Ultrasonic Method ◽  
Aqueous Media ◽  
Average Particle Size ◽  
Sodium Dodecyl ◽  
Vinyl Pyrrolidone ◽  
Average Particle ◽  
Poly Vinyl Pyrrolidone

The effects of poly (vinyl pyrrolidone)(PVP) on dispersing carbon black (CB) particles were investigated by measuring Z-average particle size, Zeta potential and centrifugal stability of CB dispersions. Addition of PVP in a dispersing medium significantly reduces the size of suspended CB particles, especially in water. The dispersing efficiency of PVP was found to have been enhanced by adding an anionic surfactant, sodium methylenedinaphthalene disulphonate (NNO) in the aqueous media. The particle size of CB dispersed with PVP and NNO was 175.7 nm, significantly smaller than that dispersed with PVP and sodium dodecyl sulfate (SDS). The performance of PVP-encapsulated CB particles and that of PVP-adsorbed CB particles were also compared. The particle size and Zeta potential of PVP-encapsulated CB particles were similar to those of PVP-adsorbed CB particles using ultrasonic method, but the centrifugal stability of PVP-encapsulated CB dispersions was significantly improved. The relative absorbency of PVP/CB dispersions was increased from 42.0% to 63.7%. However, the PVP-encapsulated layer can be destroyed by prolonged ultrasonic treatment because the ultrasound over a long period of time can not only break up the flocculation bridge in the crosslinking matrix of PVP, but also flake off the PVP shells on the surface of CB particles.

Determination of Latex Particle Size Distributions by Fractional Creaming with Sodium Alginate

1961 ◽  
Vol 34 (2) ◽  
pp. 433-445 ◽  
Author(s):  
E. Schmidt ◽  
P. H. Biddison
Keyword(s):  
Particle Size ◽  
Electron Microscope ◽  
Sodium Alginate ◽  
Mass Distribution ◽  
Average Particle Size ◽  
Average Particle ◽  
Particle Sizes ◽  
Size Distributions ◽  
Particle Size Distributions

Abstract Knowledge of mass distribution of particle sizes in latex is very important to the latex technologist. Therefore, it is desirable to have available a simple method for the determination of mass distribution of particle sizes. This paper presents a method, based on fractional creaming of latex with sodium alginate, which can be used in any laboratory without special equipment. The method is particularly advantageous for analyzing latexes of very wide particle size distributions. When analyzed with an electron microscope, these latexes require counting a very large number of particles. McGavack found that partial creaming of normal hevea latex with ammonium alginate gives concentrates of larger average particle size than the original latex. He found that the average particle size in the cream approaches that of the original latex as the amount of creaming agent is increased. In a previous paper from this laboratory, Schmidt and Kelsey demonstrated that the phenomenon of fractionation according to particle size with increasing amounts of creaming agent is applicable in a wide variety of anionic latex systems and in colloidal silica. Their results indicated also the existence of a quantitative relationship, independent of the nature of the dispersed particles, between the concentration of creaming agent and size of creamed particles. Maron confirmed fractionation with respect to particle size as a consequence of partial creaming with alginate. He showed that the mass average particle sizes of fractions, determined optically, cumulate to that of the original latex. Although the previous paper by Schmidt and Kelsey implied the basic concept of a method of determining particle size distribution by fractional creaming, it was not exploited at that time. In order to adapt the fractional creaming phenomenon to a quantitative method for particle size determination, we required a more precise knowledge of the relation between creaming agent concentration and size of particles creamed. It was proposed to establish this relationship with the aid of the electron microscope. Various factors influencing the creaming of latex, such as polymer concentration, electrolyte, soap content, and variability of the creaming agent, had to be considered in standardizing the creaming procedure.

Influence of Carbon Black on the Oxidation of Natural Rubber

1953 ◽  
Vol 26 (4) ◽  
pp. 862-868
Author(s):  
G. J. van Amerongen
Keyword(s):  
Particle Size ◽  
Carbon Black ◽  
Natural Rubber ◽  
Oxidation Reaction ◽  
Catalytic Action ◽  
Particle Sizes ◽  
Carbon Blacks ◽  
Aging Resistance ◽  
Solubility Of Oxygen

Abstract In this investigation an attempt was made to determine to what extent the solubility of oxygen in natural rubber and the aging resistance are influenced by the incorporation of carbon blacks of various particle sizes in the rubber. The influence of the particle size of carbon black on the oxidizability of GR-S loaded with carbon black had already been proved by Winn, Shelton, and Turnbull. In their explanation of this effect, carbon black was considered to be a catalyst for the oxidation reaction of rubber, although nothing was known about the nature of this catalytic action. Moreover, measurements with natural rubber were lacking.

Study of Synthesis of Nanoparticulate Zinc Oxide Aiming at the Confection of Appropriated Targets for the Production of Radioisotopes

2016 ◽  
Vol 881 ◽  
pp. 485-490
Author(s):  
Nelcy D.S. Mohallem ◽  
Juliana B. da Silva ◽  
Cristiana P. Rezende
Keyword(s):  
Particle Size ◽  
Zinc Oxide ◽  
Gamma Spectroscopy ◽  
Low Cost ◽  
Average Particle Size ◽  
Average Particle ◽  
Radioisotope Production ◽  
Target Preparation ◽  
Multifunctional Material ◽  
Freeze Dried

Zinc Oxide (ZnO) is a multifunctional material, which produces radionuclides of gallium by irradiation, widely used in diagnosis and nuclear medicine. In this work, two precursors were tested as well as two routes of synthesis, with the objective of obtaining nanoparticles appropriate to the production of pellets with grain size and porosity suitable for target preparation used in the radioisotope production by irradiation. The sintered pellets obtained from zinc acetate and NH4OH, and freeze-dried presented density of 90% of the theoretical density, average particle size of 1 μm and macropore size of 500 nm. These targets generated radionuclide of gallium (67Ga and 66Ga) inside the pores, without rupture of the pellets, confirmed by gamma spectroscopy, at low cost of production.

scholarly journals Kinetics and Photodegradation Study of Aqueous Methyltert-Butyl Ether Using Zinc Oxide: The Effect of Particle Size

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Zaki S. Seddigi ◽  
Saleh A. Ahmed ◽  
Shahid P. Ansari ◽  
Ekram Danish ◽  
Abdullah Abu Alkibash ◽  
...  
Keyword(s):  
Particle Size ◽  
Zinc Oxide ◽  
Order Reaction ◽  
Average Particle ◽  
Particle Sizes ◽  
Mercury Lamp ◽  
Butyl Ether ◽  
First Order ◽  
Effect Of Particle Size ◽  
Kinetics Of

Zinc oxide of different average particle sizes 25 nm, 59 nm, and 421 nm as applied in the photodegradation of MTBE. This study was carried out in a batch photoreactor having a high pressure mercury lamp. Zinc oxide of particle size of 421 nm was found to be the most effective in degrading MTBE in an aqueous solution. On using this type of ZnO in a solution of 100 ppm MTBE, the concentration of MTBE has decreased to 5.1 ppm after a period of five hours. The kinetics of the photocatalytic degradation of MTBE was found to be a first order reaction.

scholarly journals f INFLUENCE OF PISTACHIO SHELL POWDER REINFORCEMENT ON FTIR AND DSC BEHAVIOR OF PMMA ACRYLIC RESIN

2020 ◽  
Vol 20 (1) ◽  
pp. 63-76
Author(s):  
Jawad Kadhim Oleiwi ◽  
Jawad Kadhim Oleiwi
Keyword(s):  
Particle Size ◽  
Average Particle Size ◽  
Acrylic Resin ◽  
Average Particle ◽  
Particle Sizes ◽  
Denture Base ◽  
Pistachio Shell ◽  
Heat Cure ◽  
The Fourier Transform ◽  
Shell Powder

Although, the PMMA have good advantages made it appropriate to denture base applications. But its low impact and fracture strength represent the main drawbacks of it.so many studies had been done in order to overcome these problems. In this study Pistachio Shell powder was added in different weight fractions of about (3, 6, 9 and 12 wt. %) and different average particle sizes of about (53µm, 106µm, 150µm and212µm) to (heat-cure) PMMA that is popularly utilize in denture base applications and study the Fourier transform infrared spectroscopy (FTIR) and Differential Scanning Calorimeter (DSC) behavior of this bio composite. The results were as the following: the FTIR results demonstrated that there are no new peaks appeared after the reinforcing by Pistachio Shell powder. Also there was no shifting in any of these peaks. While the DSC test showed that the glass transition temperature (Tg) increased as the particle size of Pistachio Shell powder increased. The highest value of Tg (126.9?) was obtained for composite specimen reinforced with 12% of Pistachio Shell powder with average particle size of about (212µm).

Carbon Black in Rubber Compounding

1941 ◽  
Vol 14 (1) ◽  
pp. 98-112 ◽  
Author(s):  
D. Parkinson
Keyword(s):  
Particle Size ◽  
Carbon Black ◽  
Fine Particle ◽  
Average Particle Size ◽  
Average Particle ◽  
Small Particles ◽  
Surface Development ◽  
Fine Particle Size ◽  
Filler Reinforcement ◽  
Methods Of Measurement

Abstract The mechanism of filler reinforcement has not yet been fully explained, but there is general agreement that an important, probably the most important, factor is the enormous surface development between the rubber and filler due to the fine particle size of the filler. Explanations have been attempted to show how small particles can cause reinforcement, but a complete theory of the phenomenon which accounts for all the facts is still awaited. Particle size oj carbon blacks.—A knowledge of this property is important in an understanding of the mechanism of reinforcement by carbon black. Because of the difficulty of distinguishing between ultimate particles and compact aggregates, and because the particles themselves are too small to be resolved in an ordinary microscope, the usual microscopical methods of measurement are inapplicable. Ultramicroscopical methods have been used with some success, the results obtained by the method of Gehman and Morris being probably the most reliable. These authors quote an average particle size of 61µµ for a sample of a standard rubber gas black (Micronex). The figures given for P-33 black, Shawinigan acetylene black and Thermatomic black are 159µµ, 130µµ and 1120µµ, respectively.

TEM Study of Rhodium Catalysts with Manganese Promoter

2010 ◽  
Vol 4 (1) ◽  
Author(s):  
A. Merritt ◽  
Y. Zhao ◽  
R.F. Klie
Keyword(s):  
Particle Size ◽  
Average Particle Size ◽  
Average Particle ◽  
Particle Sizes ◽  
Rhodium Catalysts ◽  
Structural Studies ◽  
Contrast Imaging ◽  
Before And After ◽  
Z Contrast ◽  
Electron Energy Loss

The focus of this research is on studying the effects of a manganese promoter on rhodium particles for the purposes of ethanol catalysation from syngas. Through TEM imaging, the particle size has been studied both before and after reduction with and without a manganese promoter. For pure rhodium on silica, the average particle size before reduction was 3.1 ± 0.8 nm and 3.1 ± 0.8 nm after reduction. For rhodium with a manganese promoter on silica, the average particle size before reduction was 2.3 ± 0.5 nm and 2.4 ± 0.7 nm after reduction. These results point to a clear effect of manganese on the particle sizes of rhodium, but an insufficient effect on particle size to fully explain all effects of manganese promotion on rhodium catalysts. Further research will be focusing on using a JEOL-2010F to conduct electron energy loss spectroscopy (EELS) and Z-contrast imaging structural studies.

Compaction of ZrO2(Y2O3) Powders with Different Particle Sizes and Effects on the Sintering

2014 ◽  
Vol 798-799 ◽  
pp. 719-724 ◽  
Author(s):  
Camila Aparecida Araújo da Silva ◽  
Luiz Cláudio Lemos de Assis ◽  
Roberto de Oliveira Magnago ◽  
Alexandre Alvarenga Palmeira ◽  
Gabriel Rocha Lellis Villanova ◽  
...  
Keyword(s):  
Particle Size ◽  
Tetragonal Phase ◽  
Compaction Pressure ◽  
Average Particle Size ◽  
Average Particle ◽  
Particle Sizes ◽  
Green Density ◽  
Full Densification

In this work, compacting powders of different ZrO2(Y2O3) are investigated relating the particle size, compaction pressure, and use of binders. Powders of ZrO2 stabilized with 3mol % Y2O3 with an average particle size of 0.15 to 0.7μm presence of both bonding and 0.15μm without addition of binder, were uniaxially compacted with pressures of 30 to 115MPa. Green density between 40% and 50% were obtained. The results indicate that powders sized less densification above 1400°C, while the larger sizes only after reaching full densification above 1500°C. Crystallographic characterization indicates that the powders have a percentage of monoclinic phases in the range of 15% to 26%, but only after sintering tetragonal phase is identified.

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