Investigations of Rubber Fillers. I. Particle Size and Characteristic form of Carbon Blacks and Their Influence on the Properties of Rubber Mixtures, as Judged by Ultra-Microscopic Photographs

1941 ◽  
Vol 14 (4) ◽  
pp. 920-928
Author(s):  
Th. Schoon ◽  
H. W. Koch
Keyword(s):  
Particle Size ◽  
Physical Properties ◽  
The Other ◽  
Particle Sizes ◽  
Characteristic Form ◽  
Electron Microscopic ◽  
Rubber Industry ◽  
Characteristic Shape ◽  
Carbon Blacks ◽  
The Past

Abstract The particle sizes and characteristic shapes of the particles of eighteen blacks used in the rubber industry were determined. The values which were obtained are compared with the physical properties of rubber mixtures prepared from these blacks. The characteristic shape of the particles has the greatest effect on the extensibility and the rigidity at 200 per cent elongation, i.e., on the modulus. When the particle size of a black is over 100 mµ, relatively poor resistance to tearing of vulcanizates containing the black is obtained. In general, the particle size of a black has far less influence on the other physical properties than has been believed in the past. With the aid of electron microscopic photographs, it is possible to estimate the value of a black as a filler in rubber.

The physical properties of chromium oxide—aluminium oxide catalysts - III. The conversion of heptane to toluene

1954 ◽  
Vol 224 (1158) ◽  
pp. 426-433 ◽  
Keyword(s):  
Electrical Conductivity ◽  
Physical Properties ◽  
Chromium Oxide ◽  
Maximum Activity ◽  
Zero Order ◽  
Oxide Catalysts ◽  
The Other ◽  
Characteristic Form ◽  
Composition Curve ◽  
Rate Controlling Step

The activity-composition curve of co-precipitated chromium oxide-alumina catalysts for the production of toluene from heptane shows two regions of maximum activity. One, at about 70% Cr 2 O 3 is close to the maximum for chemisorption of hydrogen and is in an area where the electrical conductivity is high. The other, at about 30% Cr 2 O 3 , is associated with a change in structure. The reaction is of zero order and is retarded by hydrogen. The activa­tion energy is close to that observed for the conduction process on the reduced catalyst. It is concluded that the rate-controlling step in the reaction is the formation of the conducting centres, and that such a process explains the characteristic form of isobar observed with activated adsorption.

The influence of particle size distribution on soil physical properties

1986 ◽  
Vol 106 (3) ◽  
pp. 527-535 ◽  
Author(s):  
G. D. Towner
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Physical Properties ◽  
Size Distribution ◽  
Soil Physical Properties ◽  
The Other ◽  
Saturated Soils ◽  
Fine Silt ◽  
Significant Difference ◽  
Field Behaviour

SummaryBatcombe series soils readily break down to good tilths, Beccles series soils form cloddy seed beds that are resistant to weathering, and Stackyard series soils form unstable tilths that readily break down. The soils differ in their particle-size distribution. The proposition that such differences contributed to the differences in field behaviour was examined by forming artificial soils, each of which was made up from particles of one of the soils, but redistributed with respect to size in the proportion in which they occurred in one of the other soils.As a measure of the relevant physical properties, breaking strengths and bulk densities of cylindrical ‘clods’ moulded from the artificial soils were determined. To aid interpretation of the observed soil properties, similar measurements were made on individual fractions, on various other mixtures and on the parent soils.The breaking strengths of the soils made up to a given particle-size distribution from particles from the different parent soils were reasonably close to each other, with those for the Beccles distribution being more variable. There was a significant difference between the two. The strength of the reconstituted Batcombe soil was markedly greater than that of its parent soil, whereas that for Beccles soil was markedly less. There was little difference for the Stackyard soil.The bulk densities of saturated soils reconstituted from all nine fractions could be estimated reasonably accurately from the properties of the separate components. The structure of each of these soils in the air-dry state was inferred from comparisons between measured and calculated bulk densities. The breaking strengths of air-dry reconstituted soils were estimated from the properties of the separate components, and agreed reasonably well with the measured values for soils in which the clay and fine silt fractions predominated.Whereas it was generally possible to predict various physical properties of the reconstituted soils from those of the separate fractions, it was not possible to extrapolate the results to explain field behaviour.

Study on Physical and Dynamic Properties of BR Based Composites Filled with Different Particle Size of Magnesia

2012 ◽  
Vol 217-219 ◽  
pp. 165-173 ◽  
Author(s):  
Nai Xiu Ding ◽  
Fu Lan Hao ◽  
Lei Li ◽  
Wen Sun ◽  
Liang Liu
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Tensile Strength ◽  
Physical Properties ◽  
Dynamic Properties ◽  
Dynamic Mechanical Properties ◽  
Frequency Mode ◽  
Particle Sizes ◽  
Payne Effect ◽  
Dynamic Mechanical

BR/MgO composites were prepared with seven kinds of particle sizes of MgO filled respectively. Effects of particle sizes on dynamic mechanical properties, vulcanization characteristics and physical properties of BR/MgO composites were studied. The results showed that the tensile strength of composites filled nanoscale of MgO was nine times of pure BR, and the vulcanization time was significantly shorter than that of composites filled with micron grade filler. The RPA experiments proved that the composites filled with MgO of 20nm and 50nm have greatly higher G＇, and that the G＇of the composites increase markedly while the value of tanδ decrease sharply with given temperature above 90 °C increasing. the higher value of tanδ at the frequency mode, and the obvious Payne effect compared with the composites filled micron grade of MgO

scholarly journals Effects of processing whole oats on the analysis and fate of mycotoxins and ergosterol

2020 ◽  
Vol 13 (1) ◽  
pp. 45-56 ◽  
Author(s):  
S.A. Tittlemier ◽  
R. Blagden ◽  
J. Chan ◽  
T.L. McMillan ◽  
K. Pleskach ◽  
...  
Keyword(s):  
Particle Size ◽  
Plant Transformation ◽  
Size Fraction ◽  
Transformation Product ◽  
The Other ◽  
Particle Sizes ◽  
Particle Size Fraction ◽  
Fraction Distribution ◽  
Mycotoxin Analysis ◽  
Sample Heterogeneity

Grinding and dividing equipment were evaluated for their ability to comminute and divide ground oats in preparation for mycotoxin analysis. Four different grinders, using various settings, were evaluated for their ability to comminute oats and produce small particle sizes. Rotor beater type grinders produced the more desirable finer ground samples as compared to burr type mills. Four different division methods (manual scooping, rotary sample division, and two designs of gravity-fed dividers) were assessed for their ability to produce sub-samples with consistent particle size fraction distributions. No practical differences were observed on the particle size fraction distribution of test portions of finely ground oats produced using the four different division methods; therefore, no effects on mycotoxin analysis were anticipated. The effects of processing naturally contaminated whole oats on mycotoxin concentrations was also assessed. Laboratory scale dehulling, steaming, and kilning were examined. Dehulling showed the greatest impact and removed 60-100% of various Fusarium- and Alternaria-produced mycotoxins, as well as ergosterol, present on the naturally contaminated whole oats. Different from the other analytes studied, only 48% of the mycotoxin plant transformation product deoxynivalenol-3-glucoside was present in hulls and removed during dehulling. Steaming and kilning appeared to increase ergosterol in groats, as well as decrease deoxynivalenol and deoxynivalenol-3- glucoside. The observed inconsistent changes in concentrations of tentoxin after heat treatment of groats appeared to be due to sample heterogeneity.

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.

scholarly journals A Study on the utilization of coffee grounds for particle board

2021 ◽  
Vol 10 (2) ◽  
pp. 48-52
Author(s):  
Cut Rizka Maulida ◽  
Mursal Mursal ◽  
Ismail Ismail
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Compressive Strength ◽  
Physical Properties ◽  
Epoxy Resin ◽  
Particle Sizes ◽  
Particle Board ◽  
Thickness Swelling ◽  
Coffee Grounds ◽  
Coffee Ground

Abstrak. Penelitian ini bertujuan untuk membuat papan partikel dengan menggunakan limbah ampas kopi dan resin epoksi sebagai perekat. Komposisi resin epoksi divariasikan yaitu 5, 10, 15 dan 20 vol.% untuk masing-masing partikel ampas kopi berukuran 20 dan 40 mesh. Papan partikel dibuat dengan teknik pressing dengan beban sebesar 9 ton selama 30 menit. Sifat mekanik yang diuji adalah MOE, MOR, dan kuat tekan. Sifat fisis papan partikel yang diuji adalah kerapatan dan pengembangan tebal. Hasil menunjukkan bahwa nilai MOE tertinggi yaitu 20,910 kgf/cm2 pada komposisi 95 vol.% ampas kopi dan 5 vol.% resin epoksi dengan ukuran ampas kopi 40 mesh. MOR tertinggi yaitu 167 kgf/cm2 pada ukuran partikel 40 mesh dengan komposisi ampas kopi 90 vol.% dan resin epoksi 10 vol.%. Nilai kuat tekan tertinggi diperoleh 220 kgf/cm2 pada 20 mesh, dengan komposisi 85 vol.% ampas kopi dan 15 vol.% resin epoksi. Kerapatan dan pengembangan tebal papan partikel yang tertinggi masing-masing adalah 1,16 g/cm3 dan 0,85%. Secara umum, sifat mekanis papan partikel ampas kopi tergantung pada komposisi dan ukuran partikel ampas kopi. Namun, sifat fisisnya tidak berubah secara signifikan untuk ukuran partikel dan komposisi yang berbeda. Papan partikel yang diperoleh dari penelitian ini memenuhi standar ANSI sehingga berpotensi untuk dijadikan sebagai papan partikel atau komposit. Abstract.. This study aims to make a particle board using coffee ground waste and epoxy resin as an adhesive. The composition of the epoxy resin was varied, namely 5, 10, 15 and 20 vol.% for 20 mesh and 40 mesh of coffee grounds particles. Particle board is made by pressing technique with a load of 9 tons for 30 minutes. The mechanical properties tested were MOE, MOR, and compressive strength. The physical properties of the particle board tested were density and thickness swelling. The results showed that the highest MOE particle board was 20.910 kgf/cm2 (95 vol.% coffee grounds:5 vol.% epoxy resin; 40 mesh). The highest MOR was 167 kgf/cm2 (90 vol.% coffee grounds:10 vol.% epoxy resin;40 mesh). The hihgest compressive strength values was 220 kgf/cm2 (85 vol.% coffee grounds:15 vol.% epoxy resin;20 mesh). The highest density and thickness expansion were 1.16 g/cm3 and 0.85%, respectively. In general, the mechanical properties of coffee grounds particleboard depend on the composition and particle size of coffee grounds. However, their physical properties do not change significantly for different particle sizes and compositions. The particle board obtained from this study meets the standard of ANSI. Thus, coffee grounds have the potential to be used as particle board or composite. Keywords particle board, coffee grounds, epoxy resin, mechanical properties, physical properties

Filler Choices in the Rubber Industry

1982 ◽  
Vol 55 (3) ◽  
pp. 860-880 ◽  
Author(s):  
E. M. Dannenberg
Keyword(s):  
Particle Size ◽  
Carbon Black ◽  
Size Range ◽  
Carbon Black Particle ◽  
Silane Coupling Agents ◽  
Particle Size Range ◽  
Calcium Carbonates ◽  
Rubber Industry ◽  
Carbon Blacks ◽  
Inorganic Fillers

Abstract A wide variety of inorganic fillers are produced for the rubber industry. The most important are the clays, precipitated silicas and silicates, and the ground and precipitated calcium carbonates. The silicas and silicates provide the broadest particle size range falling into the carbon black range from FEF (N550) to finer than SAF (N110). The clays and calcium carbonates are in the larger carbon black particle size range from coarser than thermal black (N990) to FEF (N550). if particle size were the only important parameter determining the usefulness of rubber fillers, these products would meet the requirements presently served by carbon black. Their failure to be interchangeable with the carbon blacks is due to their lower modulus and reinforcement performance. These deficiencies are caused by the nature of their surfaces, which are generally more polar and hydrated than carbon black. This makes them more difficult to adhere to and interact with the rubber phase. In order to improve the surface interaction of inorganic fillers with hydrocarbon rubbers, a number of new polymer-reactive, surface-treated products have been introduced. The addition of silane coupling agents during mixing has also been recommended. Silane treated clays and talc, and polymer-grafted clay and calcium carbonate are commercially available. These products are better than their base materials. For some applications, they have been suggested as alternatives to the lower reinforcing grades of carbon black. For the higher reinforcing carbon blacks, only the precipitated silicas with silane additives can be considered as alternatives. However, in tire tread applications, the performance of these combinations has not been clearly defined, and the high cost of the silanes makes their use with silica prohibitive. A more economic method for coupling may result from recent research on functionalized polymers capable of reacting with the surface silanol groups of silica. This survey also includes two finely divided carbonaceous fillers made from coal and petroleum coke. Blends of these materials with more reinforcing carbon blacks and other fillers have been recommended as alternatives to the carbon blacks in the thermal to SRF range. A number of commercial fillers have been suggested as alternatives to the lower reinforcing grades of carbon black for some applications. There are no satisfactory substitute products for the medium to high reinforcing grades of carbon black.

Application of mineral magnetism to describe profile development of toposequences of a sedimentary soil in south-eastern Australia

Soil Research ◽  
2001 ◽  
Vol 39 (5) ◽  
pp. 927 ◽  
Author(s):  
R. H. Crockford ◽  
I. R. Willett
Keyword(s):  
Particle Size ◽  
Grain Size ◽  
Magnetic Susceptibility ◽  
Magnetic Particles ◽  
Size Range ◽  
The Other ◽  
Particle Sizes ◽  
Mineral Magnetism ◽  
Particle Size Range ◽  
Eastern Australia

Mineral magnetism and chemical properties of soil profiles across a valley with an erosion gully in a Yellow Dermosol sedimentary soil suggest that the magnetic profile resulted from a combination of alluviation and pedogenesis. The concentration of soil magnetic minerals in a range of particle sizes (3.36–2 mm to <2 μm) diminished from the surface downwards to a minimum (referred to as layer P), then increased to high values (layer H), after which it decreased to bed rock level at the base layer. It is proposed that the H layer was the surface of a buried soil, and that the ferrimagnetic mineral through the profiles was dominantly maghemite, formed by fire enhancement. The magnetic pattern of the profiles compressed as the soil became shallower up-slope, from 3 m in depth at the lowest site to 0.7 m at a site 40 m up-slope. Above this site the high susceptibility H layer was absent, which is consistent with the H layer being an earlier soil surface. Except for the profile at the very top of the slope (depth of 0.63 m), the magnetic grain size did not vary with depth. In the P layers, there was a greater proportion of paramagnetic minerals than in the other layers. The changes in magnetic susceptibility through the profiles were influenced by ferrimagnetic, paramagnetic, and canted anti-ferromagnetic material. For all depths in all profiles the magnetic susceptibility changed consistently through the particle size range, decreasing from the larger sizes to the 10–20 m size then increasing slightly to the smallest size (<2 μm). The mean magnetic grain size also decreased through the particle size range. Magnetic particles of 3 concentration levels were extracted by a hand magnet from the 4 largest particle sizes and showed the same magnetic-particle size relationships, for both mass susceptibility and magnetic grain size, as the other particle sizes. This showed that the proportion of highly magnetic particles effectively determined the susceptibility and magnetic grain size features of the bulk samples of each particle size class. The particle size/magnetic susceptibility pattern described in this paper occurs in all sedimentary soils and derived river sediments studied in this part of Australia. However, soils and sediments of granitic origin have an inverse pattern. These differences are attributed to pedogenic and geomorphological process. The difficulties in using mineral magnetic properties as a means of sourcing mobile sediments in catchments are discussed.

Technical Microscopy in the Rubber Industry

1943 ◽  
Vol 16 (1) ◽  
pp. 219-243 ◽  
Author(s):  
R. P. Allen
Keyword(s):  
Particle Size ◽  
Physical Properties ◽  
Raw Materials ◽  
Service Performance ◽  
Industrial Laboratory ◽  
Rubber Industry ◽  
Size And Shape ◽  
Properties Of Materials ◽  
Particle Size And Shape ◽  
Size Of Particles

Abstract For supplying information not obtainable by the usual methods, the microscope is useful and often essential; not only will it disclose details which would otherwise be unseen, but by its unique methods of examination measurements of certain properties of materials can be readily secured which are not otherwise obtainable. When one considers the value of the microscope to the rubber industry specifically, the study of the size of particles is usually the first and frequently the only application which comes to mind, although other uses have been suggested and described. The present paper not only describes the importance of the microscope in determining particle size and shape, but also covers its applications in the solution of other problems which ordinarily are not considered to lie in the field of microscopy. [Chamot describes many interesting applications in different industries which indicate the unusual capabilities of microscopic methods.] In a well-organized industrial laboratory, the microscope is used to supplement and aid other methods for examination of raw materials, control of factory processing, correlation of physical properties with service performance, and solution of factory difficulties. The specific examples cited in this paper represent uses which have originated in connection with the manufacture of rubber goods, but they serve also to illustrate methods applicable to problems of the same type originating in other industries.

Online analysis of macrostickies in a sorted office waste recycling plant making tissue

TAPPI Journal ◽  
2014 ◽  
Vol 13 (4) ◽  
pp. 47-55
Author(s):  
MICHELLE RICARD ◽  
GILLES M. DORRIS ◽  
NATALIE PAGÉ ◽  
DENISE FILION
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Distribution Patterns ◽  
Waste Recycling ◽  
The Other ◽  
Particle Sizes ◽  
Flotation Cell ◽  
Wide Range ◽  
Removal Efficiencies ◽  
Office Waste

An online macrocontaminant analyzer, the FPAutoSpeck, was used for 8000 measurements of deinked pulp to determine the number and area of heavy stickies, light macrocontaminants, and dirt. The analyzer detected a wide range of macrocontaminant levels, during which the three types of macrocontaminants varied independently of each other. “Stickies storm” levels were detected and visualized by the analyzer, with heavy stickies levels exceeding 17000/kg in the final pulp. Different particle size distribution patterns were noted for the light macrocontaminants when compared to those obtained for heavy stickies and dirt. Mill surveys of the fine screens and flotation cell showed different removal efficiencies for heavy stickies and light macrocontaminants. Fine screening was slightly more efficient in the removal of heavy stickies than of light macrocontaminants. Fine screens were more efficient at removing heavy stickies with particle sizes larger than 400 μm in diameter. On the other hand, flotation could remove heavy stickies with particle sizes of 200-300 μm. Furthermore, flotation was able to remove most of the light macrocontaminants independent of their particle size.

Sign in / Sign up

Export Citation Format

Share Document