The Role of Zinc Oxide in Compounding Government Synthetic Rubber

Abstract A comparative analysis of some of the factors involved in road tests on tires and laboratory flexometer tests indicates that not enough attention has been paid to heat dissipation and the role of the thermal conductivity of stocks in increasing heat dissipation. Flexometer tests currently used, in which samples are flexed between insulated plates, measure mainly heat generation. A modified St. Joe flexometer test is described, using metal-faced plates, which takes into account not only heat generation but heat dissipation, and should more nearly simulate road tests on tires when comparing GR-S (Buna-S) synthetic rubber stocks having different thermal conductivities. Using the new type test, mixtures of easy-processing channel black and zinc oxide are shown to have higher tensile strength and lower heat generation than soft blacks or mixtures of soft blacks and easy-processing channel blacks. The data given in this report indicate the need of further work along this line in the way of road tests on actual GR-S (Buna-S) tires containing zinc oxide in both tread and carcass.

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The Effects of Material Properties on Heat Dissipation in High Power Electronics

Journal of Electronic Packaging ◽

10.1115/1.2792634 ◽

1998 ◽

Vol 120 (3) ◽

pp. 280-289 ◽

Cited By ~ 13

Author(s):

T. J. Lu ◽

A. G. Evans ◽

J. W. Hutchinson

Keyword(s):

Thermal Conductivity ◽

Power Electronics ◽

High Power ◽

Heat Dissipation ◽

Substrate Material ◽

High Thermal Conductivity ◽

Analytical Models ◽

Wide Range ◽

Power Densities

The role of the substrate in determining heat dissipation in high power electronics is calculated, subject to convective cooling in the small Biot number regime. Analytical models that exploit the large aspect ratio of the substrate to justify approximations are shown to predict the behavior with good accuracy over a wide range of configurations. The solutions distinguish heat spreading effects’ that enable high chip-level power densities from insulation effects that arise at large chip densities. In the former, the attributes of high thermal conductivity are apparent, especially when the substrate dimensions are optimized. Additional benefits that derive from a thin layer of a high thermal conductivity material (such as diamond) are demonstrated. In the insulating region, which arises at high overall power densities, the substrate thermal conductivity has essentially no effect on the heat dissipation. Similarly, for compact multichip module designs, with chips placed on both sides of the substrate, heat dissipation is insensitive to the choice of the substrate material, unless advanced cooling mechanisms are used to remove heat around the module perimeter.

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Thermal Analysis of Multifunctional Satellite Structure-Battery

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.450-451.228 ◽

2012 ◽

Vol 450-451 ◽

pp. 228-234

Author(s):

Yang Wang ◽

Chao Yi Peng

Keyword(s):

Thermal Conductivity ◽

Heat Dissipation ◽

Lithium Ion ◽

Thermal Control ◽

Maximum Temperature ◽

Satellite Structure ◽

Working Environments ◽

Two Parameters ◽

Longitudinal Thermal Conductivity

To make the rapidly developing micro-satellite further smaller and lighter, based on gel polymer lithium-ion battery and high thermal conductivity carbon fiber reinforced epoxy resin composites and polymethacrylimide (PMI) foam, a kind of multifunctional satellite structure-battery (SB) is designed in the paper, and an investigation of its thermal property in certain working environments is carried out by numerical simulation approach. The role of two parameters, longitudinal thermal conductivity of carbon fibers and the heat dissipation area, play in the temperature distribution while the SB is working, is analyzed. The result shows that, enlarging the heat disspation area is an effective way to decrease the maximum temperature of SB and it also implys that by selecting the two parameters carefully, the largest temperature rising of the SB could be considerably lowered, alleviating the burden of satellite thermal control subsystem.

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Investigation of the Thermal Conductivity of Rubber

Rubber Chemistry and Technology ◽

10.5254/1.3546368 ◽

1938 ◽

Vol 11 (2) ◽

pp. 359-371 ◽

Cited By ~ 2

Author(s):

L. Frumkin ◽

Yu Dubinker

Keyword(s):

Thermal Conductivity ◽

Zinc Oxide ◽

Carbon Black ◽

Natural Rubber ◽

Considerable Increase ◽

Large Percentage ◽

K Value ◽

Synthetic Rubber ◽

Coefficient Of Thermal Conductivity

Abstract 1. The apparatus for the determination of the coefficients of thermal conductivity which is described is satisfactory for the investigation of rubber mixtures. 2. A review of the results of the determinations of K values of various mixtures leads to the following conclusions: (a) The thermal conductivity of rubber mixtures containing synthetic rubber is greater than that of mixtures containing natural rubber. (b) The addition of zinc oxide even in considerable quantities to rubber mixtures containing a large percentage (55 per cent) of carbon black does not substantially increase thermal conductivity. (c) In the case of carcass mixtures a considerable increase in the coefficient of thermal conductivity is observed when the content of zinc oxide is increased from 7.5 to 15 per cent by weight; on further increase in the zinc oxide K increases but little. (d) The K value of carcass mixtures before vulcanization is smaller than that of the same mixtures after vulcanization by an average of 23 per cent. (e) The thermal conductivity of uncured tread mixtures is the same as that of vulcanized mixtures. (f) The coefficient of vulcanization has no effect on the K value of unloaded mixtures and mixtures containing fillers. (g) The K value of rubber mixtures increases sharply with addition up to 60 per cent by volume of fillers with good thermal conductivity (zinc oxide and graphite), but only slowly with the addition of fillers of medium thermal conductivity (carbon black). In other words, the curve of the relation between the coefficient of thermal conductivity and the percentage by volume of graphite and of zinc oxide is convex to the filler axis and is concave in the case of carbon black.

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Thermal conductivity of V2O5 nanowires and their contact thermal conductance

Nanoscale ◽

10.1039/c9nr08803b ◽

2020 ◽

Vol 12 (2) ◽

pp. 1138-1143 ◽

Cited By ~ 3

Author(s):

Qilang Wang ◽

Xing Liang ◽

Bohai Liu ◽

Yihui Song ◽

Guohua Gao ◽

...

Keyword(s):

Thermal Conductivity ◽

Thermal Resistance ◽

Heat Dissipation ◽

Thermal Conductance ◽

Vital Role ◽

Interfacial Thermal Resistance ◽

Li Ion Batteries ◽

Thermal Measurements ◽

Li Ion

Thermal measurements of V2O5 nanowires suggest the vital role of interfacial thermal resistance in the heat dissipation in Li-ion batteries.

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Study on Performance Optimization and Physical Properties Testing of a New Type of High Thermal Conductive Damping Coating

Journal of Physics Conference Series ◽

10.1088/1742-6596/2083/2/022001 ◽

2021 ◽

Vol 2083 (2) ◽

pp. 022001

Author(s):

Wei Chen ◽

Sheng Hu ◽

RuiDun Zhao ◽

Yine Xie ◽

Hao Cao

Keyword(s):

Thermal Conductivity ◽

Performance Optimization ◽

Heat Dissipation ◽

Fiber Type ◽

Conductive Filler ◽

Sound Insulation ◽

Acrylic Emulsion ◽

Network Chain ◽

Thermally Conductive ◽

New Type

Abstract Surface coating of damping paint is a common method to suppress structural vibration and reduce noise, but damping paint has poor thermal conductivity which limits it’ s application to transformers, reactors and other equipment that have high requirements for heat dissipation. In this paper, a new type of high thermal conductivity damping coating is prepared by emulsion polymerization, among which, a polyurethane emulsion with internal cross-linking structure and an acrylic emulsion with polymerization function are used as main agents, mica powder is used as the main damping function filler. By adjusting the proportion of non-metallic thermal conductive filler Al2O3 and thermal conductive fiber to explore the influence of different thermal conductive fillers on the thermal conductivity and damping performance of the damping coating. The paint is applied to aluminum and iron plates, and the sound insulation capacity is tested to study the influence of paint thickness, fiber addition, fiber type, viscoelasticity, and temperature aging on the sound insulation performance of damping sound insulation panels. The test results show that by adding thermally conductive filler Al2O3 and thermally conductive fibers, a thermally conductive network chain is formed inside the damping coating, which greatly improves the thermal conductivity of the coating while ensuring the damping performance and the effect of vibration and noise reduction.

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Analysis Of Temperature Profile And Efficiency Of Convective Straight Fins With Temperature Dependent Thermal Conductivity And Internal Heat Generation

10.26678/abcm.cobem2017.cob17-2214 ◽

2017 ◽

Author(s):

Luiz Ferreira ◽

Marcos Curi ◽

Luiz Chaves

Keyword(s):

Thermal Conductivity ◽

Temperature Profile ◽

Heat Generation ◽

Internal Heat ◽

Internal Heat Generation ◽

Temperature Dependent ◽

Temperature Dependent Thermal Conductivity

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Lattice Thermal Conductivity Modelling of a Diatomic Nanoscale Material

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681209666190423142040 ◽

2020 ◽

Vol 10 (5) ◽

pp. 602-609

Author(s):

Adil H. Awad

Keyword(s):

Thermal Conductivity ◽

Lattice Thermal Conductivity ◽

Phonon Scattering ◽

Correction Term ◽

Nanoscale Material ◽

New Approach ◽

Two Samples ◽

Conductivity Modelling ◽

Callaway Model

Introduction: A new approach for expressing the lattice thermal conductivity of diatomic nanoscale materials is developed. Methods: The lattice thermal conductivity of two samples of GaAs nanobeam at 4-100K is calculated on the basis of monatomic dispersion relation. Phonons are scattered by nanobeam boundaries, point defects and other phonons via normal and Umklapp processes. Methods: A comparative study of the results of the present analysis and those obtained using Callaway formula is performed. We clearly demonstrate the importance of the utilised scattering mechanisms in lattice thermal conductivity by addressing the separate role of the phonon scattering relaxation rate. The formulas derived from the correction term are also presented, and their difference from Callaway model is evident. Furthermore their percentage contribution is sufficiently small to be neglected in calculating lattice thermal conductivity. Conclusion: Our model is successfully used to correlate the predicted lattice thermal conductivity with that of the experimental observation.

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