Optimum formulation derivation for the ultimate packing fraction using monodispersed particle sizes when optimizing suspension viscosities

2019 ◽  
Vol 48 (1) ◽  
pp. 45-56
Author(s):  
Richard D. Sudduth
Keyword(s):  
Particle Size ◽  
Average Particle Size ◽  
Packing Fraction ◽  
Size Ratio ◽  
Average Particle ◽  
Particle Sizes ◽  
Monodisperse Particle ◽  
Content Type ◽  
Particle Size Ratio ◽  
Minimum Number

Purpose The importance of maximizing the particle packing fraction in a suspension by maximizing average particle size ratio of D5/D1 has been adequately shown to be important as previously reported in the literature. This study aims to extend that analysis to include the best formulation approach to maximize the packing fraction with a minimum number of monodisperse particle sizes. Design/methodology/approach An existing model previously developed by this author was modified theoretically to optimize the ratio used between consecutive monodisperse particle sizes. This process was found to apply to a broad range of particle configurations and applications. In addition, five different approaches for maximizing average particle size ratio D̅5/D̅1 were addressed for blending several different particle size distributions. Maximizing average particle size ratio D̅5/D̅1 has been found to result in an optimization of the packing fraction. Several new concepts were also introduced in the process of maximizing the packing fraction for these different approaches. Findings The critical part of the analysis to maximize the packing fraction with a minimum number of particles was the theoretical optimization of the ratio used between consecutive monodisperse particle sizes. This analysis was also found to be effectively independent of the maximum starting particle size. This study also clarified the recent incorrect claim in the literature that Furnas in 1931 was the first to generate the maximum theoretical packing fraction possible for n different particles that was actually originally developed in conjunction with the Sudduth generalized viscosity equation. In addition, the Furnas generated equation was also shown to give significantly different results from the Sudduth generated equation. Research limitations/implications Experimental data involving monodisperse particles of different blends with a minimum number of particle sizes that are truly monodisperse are often extremely difficult to obtain. However, the theoretical general concepts can still be applicable. Practical implications The expanded model presented in this article provides practical guidelines for blending pigments using a minimum number of monodisperse particle sizes that can yield much higher ratios of the particle size averages D̅5/D̅1 and thus potentially achieve significantly improved properties such as viscosity. Originality/value The model presented in this article provides the first apparent guidelines to control the blending of pigments in coatings by the optimization of the ratio used between consecutive monodisperse particle sizes. This analysis was also found to be effectively independent of the maximum starting particle size.

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.

Synthesis and properties of novel self-crosslinked cationic fluorinated acrylic latex prepared with novel emulsified system

2016 ◽  
Vol 45 (4) ◽  
pp. 259-264
Author(s):  
Wen Li ◽  
Zhongbin Bao ◽  
Lijun Chen ◽  
Dongshun Deng
Keyword(s):  
Particle Size ◽  
Gemini Surfactants ◽  
Average Particle Size ◽  
Water Soluble ◽  
Average Particle ◽  
Mixed Surfactants ◽  
The Novel ◽  
Content Type ◽  
Acrylic Latex ◽  
Emulsion Polymerisation

Purpose At present, the conventional method of preparing cationic fluorinated acrylic latex is to emulsify copolymerised monomers with cationic surfactants. However, there has been a wide concern about using Gemini surfactants to prepare cationic polymer latex to improve its properties. The purpose of this paper was to focus on the synthesis of novel self-crosslinked cationic fluorinated acrylic latex (SCFAL), during which the copolymerised monomers were initiated with a water soluble azo initiator and emulsified with mixed surfactants of Gemini emulsifier and alkyl polyglycoside (APG). Design/methodology/approach The novel SCFAL was prepared successfully by the semi-continuous seeded emulsion polymerisation of butyl acrylate, methyl methacrylate, hexafluorobutyl methacrylate (HFMA) and hydroxy propyl methacrylate (HPMA) in aqueous medium. Findings The conversion is the maximum and the coagulation percentage the minimum when the amounts of emulsifier and initiator are 8 and 0.6 per cent, respectively. The average particle size of the latex is significantly reduced with the increase of the amount of emulsifiers used. However, the average particle size of the latex is increased with the increase of the amount of HPMA. The particle size of the latex is of a unimodal distribution, which means that the particle size was reasonably uniform. Contact angle is increased with the increase of the amount of the HFMA. Practical implications The novel SCFAL can be widely used as significant components in the field of coatings, leather, textile, paper, adhesives and so on. Originality/value SCFAL, which was emulsified with novel mixed surfactants of Gemini surfactant and APG, has been prepared successfully. Influences of amount of initiator, emulsifier, HPMA and HFMA on emulsion polymerisation and/or properties of novel latex are investigated in detail.

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.

Slurry erosion performance study of HVFS sprayed Ni-20Al2O3 and Ni-15Al2O3-5TiO2 coatings under hydro accelerated conditions

2018 ◽  
Vol 70 (4) ◽  
pp. 805-817 ◽  
Author(s):  
Rajeev Kumar ◽  
Sanjeev Bhandari ◽  
Atul Goyal ◽  
Yogesh Kumar Singla
Keyword(s):  
Particle Size ◽  
Rotational Speed ◽  
Average Particle Size ◽  
Synergetic Effect ◽  
Average Particle ◽  
Flame Spray ◽  
Slurry Erosion ◽  
Content Type ◽  
Slurry Concentration ◽  
Ca6nm Steel

Purpose This paper aims to cover all the aspects of development, investigation and analysis phases to evaluate the slurry erosion performance of test coatings. The powders having composition of Ni-20Al2O3 and Ni-15Al2O3-5TiO2 were deposited on CA6NM grade turbine steel by using high velocity flame spray (HVFS) technique. The characterization of the coatings was done with the help of SEM/EDS and XRD techniques. Various properties such as micro-hardness and bonding strength of the coatings were also evaluated. Thereafter, these coatings were subjected to an indigenously developed high speed slurry erosion tester at different levels of rotational speed, erodent particle size and slurry concentration. The effect of these parameters on the erosion behavior of coatings was also evaluated. The slurry erosion tests and SEM of the eroded surfaces revealed remarkable improvement in slurry erosion resistance of Ni-15Al2O3-5TiO2 coating in comparison with Ni-20Al2O3 coating. Design/methodology/approach Two different compositions of HVFS coating were developed onto CA6NM steel. Subsequently, these coatings were evaluated by means of mechanical and microstructural characterization. Further, slurry erosion testing was done to analyze the erosive wear behavior of developed coatings. Findings The coatings were successfully developed by HVFS process. Cross-sectional microscopic analysis of sprayed coatings revealed a continuous and defect-free contact between substrate and coating. Ni-15Al2O3-5TiO2 coating showed higher value of bond strength in comparison with Ni-20Al2O3 coating. Under all the testing conditions, Ni-15Al2O3-5TiO2 coatings showed higher resistance to slurry erosion in comparison with Ni-20Al2O3 coatings. Rotational speed, average particle size of erodent and slurry concentration were found to have proportional effect on specific mass loss of coatings. The mixed behavior (brittle as well as ductile) of the material removal mechanism was observed for the coatings. Originality/value From the literature review, it was found that researchers have documented the various studies on Ni-Al2O3, Ni-TiO2 and Al2O3-TiO2 coatings. No one has ascertained the synergetic effect of Alumina and Titania on the slurry erosion performance of Nickel-based coating. In view of this, the authors have developed Ni-Al2O3 and Ni-Al2O3-TiO2 coatings, and an attempt has been made to compare their mechanical, microstructural and slurry erosion characteristics.

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).

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.

New thermal deblocking characterisation method of aqueous blocked polyurethane

2014 ◽  
Vol 43 (4) ◽  
pp. 194-200 ◽  
Author(s):  
Yanhua Zhang ◽  
Jun Cao ◽  
Haiyan Tan ◽  
Jiyou Gu
Keyword(s):  
Particle Size ◽  
Average Particle Size ◽  
Wood Adhesive ◽  
Infrared Spectrometry ◽  
Particle Analysis ◽  
Average Particle ◽  
Content Type ◽  
Wood Processing ◽  
Blocking Rate ◽  
Blocked Isocyanate

Purpose – The mechanisms of the deblocking reaction of the polyurethane with blocking agent were investigated in detail relatively using thermogravimetric analysis (TGA), Fourier transform infrared spectrometry (FTIR) and X-ray photoelectron spectroscopy (XPS). This kind of method for polyurethane as the application of wood adhesives can provide the conditions of application and the main theoretical basis. Design/methodology/approach – The blocking rate and latex particle size distribution were determined using the titrimetric analysis and the laser particle analysis, respectively. TGA, FTIR, XPS and differential scanning calorimetry were used to investigate the deblocking temperature and time of the blocked isocyanate in detail. Findings – The results indicated that the blocking rate was approximately 97 per cent and the average particle size was 360 nm. The results of laser particle analysis have confirmed that the dispersivity of the blocked polyurethane emulsion was good. XPS results showed that the amount of –O = C-N-benzyl groups increased with an increasing deblocking temperature and subsequently reached equilibrium. In summary, the blocked isocyanate was deblocked at temperatures ranging from 50 to 90°C. Research limitations/implications – An important approach in future wood adhesive work would be to gain access to man-made board application data. Practical implications – The paper provided some useful information about deblocking mechanisms of blocked polyurethane that would be helpful to guide applied practical applications as wood adhesive. Social implications – To promote China’s wood processing technology progress and solve the problem of shortage of the natural quality of wood is of important practical significance. Originality/value – The paper is the first to use the XPS characterisation method to characterise deblocking polyurethane solution.

scholarly journals Evaluation of different fly ash samples on the production of alkali-activated materials

2021 ◽  
Vol 14 (6) ◽  
Author(s):  
Adriano Galvão Souza Azevedo ◽  
Luis Fernando Tonholo Domingos ◽  
Kurt Strecker
Keyword(s):  
Particle Size ◽  
Fly Ash ◽  
Mechanical Strength ◽  
Average Particle Size ◽  
Average Particle ◽  
Particle Sizes ◽  
Curing Time ◽  
Specific Mass ◽  
Fe2o3 Content ◽  
Alkali Activated

abstract: In this work, different samples of fly ash (FA-A and FA-B) classified as type F as used to produce the AAM samples. The FA-A presented a higher Fe2O3 content than FA-B, 6.1 to 3.8 wt.%, and a slightly higher SiO2/Al2O3 ratio of 3.52 in comparison to 3.34 of FA-B. The average particle size (D50) of fly ash A was 19.7 µm and of fly ash B 30.8 µm, while the specific mass of the ashes A and B were 2.38 and 2.21 g/cm3, respectively. The results revealed that the mechanical strength of the AAM produced with fly ash A was higher than fly ash B, close to 80 and 44 MPa, respectively. The variation of the strength has been attributed to the different SiO2/Al2O3 ratios and different particle sizes. The mechanical strength decreased with increasing curing time, which is attributed to excess alkali in the system. Only very small differences in porosity and density have been found.

Preparation of thermal transfer ink using disperse fluorescent yellow 82 for polyester substrates

2014 ◽  
Vol 43 (2) ◽  
pp. 92-96 ◽  
Author(s):  
Yufei Xiu ◽  
Qiankun Shen ◽  
Fei Fan ◽  
Chaoxia Wang
Keyword(s):  
Particle Size ◽  
Image Quality ◽  
Diethylene Glycol ◽  
Ph Value ◽  
Average Particle Size ◽  
Average Particle ◽  
Polyester Fabrics ◽  
Content Type ◽  
Thermal Transfer ◽  
Line Image

Purpose – A disperse fluorescent yellow paste was mixed with a dispersant naphthalene sulfonic derivative via wet grinding process to prepare thermal transfer ink with good fluorescence. The paper aims to discuss these issues. Design/methodology/approach – The surface tension, viscosity, pH value, zeta potential, stability and the morphology of ink samples were tested after the storing process. Findings – The morphology of paste was homogeneous nearly spherical nanoparticles and the particle size was about 100 nm from the transmission electron microscopy (TEM), which was similar to the average particle size obtained from the particle size analyser. Research limitations/implications – The paste particle size was 126.8 nm after storing at 50°C for one week. The addition of diethylene glycol was conducive to high fluorescent reflectivity and gave good line image quality both in warp and weft directions due to the low viscosity. Inkjet printed polyester fabrics achieved excellent rubbing, laundering and thermal subliming fastnesses. Originality/value – The polyester fabrics thermal transferred with the ink contained diethylene glycol represented higher fluorescent reflectivity and gave better line image quality both in warp and weft directions. The inkjet printed polyester fabrics showed excellent colour reproducibility and all the fastnesses, including rubbing, laundering and thermal subliming, were higher than Grade 4.

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