Dielectric constant, power factor and resistivity of rubber and gutta-percha by Curtis, Harvey Lincoln

Cover of: Dielectric constant, power factor and resistivity of rubber and gutta-percha | Curtis, Harvey Lincoln

Published by Govt. Print. Off. in Washington .

Written in English

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Subjects:

  • Rubber,
  • Gutta-percha

Edition Notes

Running title: Electrical properties of rubber

Book details

Other titlesElectrical properties of rubber
Statementby H.L. Curtis, Senior Physicist [and] A.T. McPherson, Associate Chemist, Bureau of Standards. October 23, 1925 ..
Series[United States] Bureau of Standards. Technologic papers -- no. 299
ContributionsMcPherson, Archibald Turner, 1895- joint author
The Physical Object
Pagination1 p. l., p. 669-722 incl. illus., tables, diagrs.
Number of Pages722
ID Numbers
Open LibraryOL15471360M
LC Control Number25027486

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Suitabilityofrubber,rubbercompounds,andgutta-perchaforsub- marine-cable hasconsisted in the measurement of the dielectric constant, power factor, and resistivity on specimens which. Dielectric Constant, Power Factor, and Resistivity of Rubber and Gutta-Percha: Technological Papers of the Bureau of Standards, No.

[Curtis, H. L., McPherson, A. T., Department of Commerce, National Bureau] on *FREE* shipping on qualifying offers. Dielectric Constant, Power Factor, and Resistivity of Rubber and Gutta-Percha: Technological Papers of Author: H.

Curtis, A. McPherson. The dielectric constant of dried gutta-percha ranges from to Resistivity of dried gutta-percha ranges from 25 x 10 14 to x 10 14 ohm-cm.

Since aboutpolyethylene has supplanted gutta-percha as an electrical insulator. [citation needed] Other. Dielectric constant, power factor and resistivity of rubber and gutta-percha / By Harvey Lincoln Curtis, joint author. Archibald Turner McPherson and United States. National Bureau of Standards.

Technologic Papers. Abstract. Issued as part of Technologic Papers of the Bureau of Standards, Vol Thedielectricconstant,powerfactor,andresistivityofanumber of samples of rubber and gutta-percha whichwere stored under water have beenobservedover a period of aboutseven years.

Dissipation Factor power factor and resistivity of rubber and gutta-percha book Power Factor)— This is a measure of the dielectric losses in an electrical insulating liquid when used in an alternating electric field and of the energy dissipated as heat. A low dissipation factor or power factor indicates low ac dielectric losses.

Dissipation factor or power factor may be useful as a means of quality control, and as an indication of changes in. Values presented here are relative dielectric constants (relative permittivities).

As indicated by e r = for a vacuum, all values are relative to a vacuum. Multiply by ε 0 = x F/m (permittivity of free space) to obtain absolute permittivity. Dielectric constant is a measure of the charge retention capacity of a medium. Dielectric Constant and Power Factor The dielectric constant, or specific inductive capacity (SIC), is a measure of an insulator’s ability to store electrical energy.

The dielectric constant is the ratio of the electrical capacity of a condenser using the elastomer under test as the dielectric, to the capacity of a similar condenser using air.

Poly Olefin Structure and Dielectric Behavior • Dielectric constant can be expressed for these nearly non-polar polymers by an expression of the form: e = A + B(d - da) Where, B is a constant, d is the density and da is the density at which the dielectric constant is equal to A.

Dielectric constants for this equation fit a large number of. Material Formula Dielectric constant @1kHz Dielectric constant @1MHz Dielectric strength kV mm-1 Dissipation factor @ 1kHz Dissipation factor @ 1MHz Surface resistivity Ohm/sq Volume resistivity Ohm/cm Cellulose Acetate CA - ~5 11 - - 5 x Cellulose Acetate Butyrate CAB - 10.

The dielectric constant is related to the resistivity by the Dielectric constant log R 10 K = 23 − 2 ε 1 K i.e.

the electrical resistance of polymers decreases exponentially with increasing dielectric constant. As power factor and resistivity of rubber and gutta-percha book earlier, with the incorporation of chitosan, the polarity of the system increases.

A number of samples of rubber and gutta-percha were stored under water for about seven years and electrical measurements made on them periodically to determine the effect of aging on the resistivity, dielectric constant, and power factor.

The dielectric constant was measured under three different conditions, namely, 60 cycles alternating. We measured the relative dielectric constant and dielectric loss of three coal samples under conditions of 0–80 °C and – MHz using the ultra-wideband dielectric spectrum.

The behavior of resistivity and dielectric constant described in the preceding sections seems to be intimately associated with the presence of water in the cores.

As a further check on this, measurements of dielectric constant and resistivity were made on the same group of cores after their fluid contents ^had been removed.

Insulating Oil Resistivity Meter,Dielectric Constant Test,Tan-Delta Dissipation Factor Oil Test Set: code is ; box with foam inside, fumigation,not influence the delivery; rd of CE ISO IEC. be delivered by air,ship and express.

PCS/1*20'ft Port. James G. Speight PhD, DSc, in Handbook of Industrial Hydrocarbon Processes, Electrical properties. Resistivity of a material is the resistance that a material presents to the flow of electrical charge. Dielectric strength is the voltage that an insulating material can withstand before breakdown occurs.

It usually depends on the thickness of the material and on the method and. Undersimilarcircumstances,thepowerfactorincreasedfromXforthe rubberalone to a maximum of X10 -3for the compound containing percentsulphur; it thendecreased to about X 10~ 3 at 20percent sulphur, and.

Various factors such as dielectric strength plus volume and surface resistivity are crucial to gauge the nature of the polymer material, specifically regarding its efficiency and conductivity. Electrical Properties Testing Capabilities for Polymers include: Dielectric Constant/Dissipation Factor.

↑ Curtis, H.L. Dielectric Constant, Power Factor and Resistivity of Rubber and Gutta_Percha (PDF) (Report). United States N.I.S.T. ↑ Green, Michael S. Politics and America in Crisis: The Coming of the Civil War. Santa Barbara, CA: ABC-CLIO.

ISBN – via Google Books. Dielectric Constant (DC) and Dissipation Factor (DF) ASTM D, IEC Dielectric Constant is used to determine the ability of an insulator to store electrical energy. The dielectric constant is the ratio of the capacitance induced by two metallic plates with an insulator between them to the capacitance of the same plates with air or a.

Power factor indicates the dielectric loss of oil and, thus, its dielectric heating. The power factor test is widely used as an acceptance and preventive maintenance test for insulating oil. Oil power factor testing in the field is usually done with the Doble type MH or M2H test set in conjunction with power factor.

Resistivity or conductivity may be used to predict, indirectly, the low-frequency dielectric breakdown and dissi-pation factor properties of some materials.

Resistivity or conductivity is often used as an indirect measure of: moisture content, degree of cure, mechanical continuity, or deterioration of.

The Relationship Between Loss, Conductivity, and Dielectric Constant General Expressions The question has been asked how loss, conductivity, and dielectric constant are interrelated.

Answering this question requires a fairly extensive review of basic electromagnetics. First, assume that one has a piece of arbitrary material. This material is. PHYSICAL PROPERTIES Specific gravity: Refractive index: Coefficient of cubical expansion: /°C Cohesive energy density: Cal/cc.

Heat of combustion: Cal/g Thermal conductivity: Cal/sec/cm/°C Dielectric constant: Power factor (at cycles): Volume resistivity: dielectric strength of an epoxy is roughly volts/mil at 23°C for an insulating product.

As a practical example, if an electronic circuit needs to resist volts, a minimum of 2 mil of dielectric epoxy is required. Volume resistivity, dielectric constant and dissipation factor can be experimentally determined by an adhesive manufacturer.

The dielectric constant epsilon and the conductivity are two independent parameters of an electrical material. The dielectric constant is due to polarization of immobile charges in materials which. Such cables require protective covering like lead sheath because this insulating material is hygroscopic.

Its dielectric strength is 4 kV/mm and its dielectric constant is to Such cables do not require sealing. Material # 8. Gutta-Percha: It is similar to rubber but it becomes soft at about 65°C.

values of the dielectric constant (approximately less than 20), there is a lot of change of the reflection coefficient for a small change of the dielectric constant. In this range dielectric constant measurement using the reflection coefficient will be more sensitive and hence precise.

Conversely, for high. D Test Method for Dissipation Factor (or Power Factor) and Relative Permittivity (Dielectric Constant) of Electrical Insulating Liquids.

D Test Method for Acid and Base Number by Color-Indicator Titration. D Test Method for Specific Resistance (Resistivity) of. The Dielectric Constant, or permittivity - ε - is a dimensionless constant that indicates how easy a material can be polarized by imposition of an electric field on an insulating material.

The constant is. the ratio between the actual material ability to carry an alternating. dielectric constants of less than 3. Power Factor (alternating current) The power factor is a measure of the energy absorbed by the material as the alternating current constantly changes direction and the dipoles try to align themselves with the field.

As the dipoles. The dielectric constant of paper varies from 2 to 5. Dielectric Strength: of an insulating material is the maximum electric field strength that it can withstand intrinsically without breaking down. Dielectric strength of Waxed paper is Million Volt/m or KV/mm. For a paper of mm thick, the dielectric strength will be KV.

Gutta-percha This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. Find sources: "Gutta-percha" – news newspapers b.

The dielectric material has only some electrons in normal operating condition. When the electric strength is increased beyond a particular value, it results in breakdown.

That is, the insulating properties are damaged and it finally becomes a electrical field strength at the time of breakdown is called breakdown voltage or dielectric strength.

Dielectric Constant (DC) and Dissipation Factor (DF) according ASTM D, IEC Scope: Dielectric Constant is used to determine the ability of an insulator to store electrical energy. The dielectric constant is the ratio of the capacitance induced by two metallic plates with an insulator between them to the capacitance of the same plates.

Section Power Factor and Dielectric Constant of Liquid Adhesives 7 Direct-Current Conductivity 8 Extract Conductivity 9 Acidity and Alkalinity 10 pH Value 11 Section Power Factor and Dielectric Constant of a Dried or Cured Adhesive Film 12 Dielectric Strength 13 Volume and Surface Resistivity 14 Arc Resistance Journal of Research of the National Bureau of Standards.

This banner text can have markup. The arrows represent a shift by a factor of 20, to indicate the comparable temperature dependence of the s inset shows representative spectra; the dielectric peak was shifted horizontally and multiplied by the indicated factor to superpose the peak maxima.

Data from ref 7. 34 RUBBER CHEMISTRY AND TECHNOLOGY, Vol. 89, No. 1, pp. 32–53 (). The capacitance created by the presence of the material is directly related to the Dielectric Constant of the material.

Knowing the Dielectric Constant (k) of a material is needed to properly design and apply instruments such as level controls using radar, RF admittance, or capacitance technologies. Rubber containing 20 per cent, carbon has a const and its power factor is more than twenty-five times greater than that of pure rubber.

The resistivity ranges from ioM to 10" ohm-cm. for both rubber and gutta-percha, and is not greatly changed by vulcanisation, or by most compounding ingredients. Cable insulation will be an extruded layer of XLPE, Elastomer, Rubber or PVC applied over conductor screen under triple extrusion process along with conductor screen and insulation screen; There are different Type of Insulation Material used for cable but widely used are XLPE, PVC, Elastometer, EPR & Rubber.Where A = plate area, d = distance between plates, and ɛ = dielectric material constant.

Also note that: ɛ = relative dielectric constant x dielectric constant of vacuum = ɛr x ɛ0 Where: ɛr is a plain number, ɛ0 = x 10 F/m This general formula shows that: 1.

the larger the plate area, the larger the capacitance value 2.A comparison of volume resistivity with other resins is shown in Fig. 5・2‐1. Fig. 5・2‐1 Volume resistivity of various resins (ASTM-D) 5・3 Dielectric Constant and Dielectric Dissipation Factor The dielectric constant and dielectric dissipation factor of Iupilon / NOVAREX are ASTM-DT, 50Hz, normal temperature.

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