bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effect of Grit upon the Stress and Strain Properties of a Carbon Black Stock
Authors: Kearsley E. P. W. , Park C. R. 
Published: February 2011

Abstract
Numerous papers have appeared from time to time dealing with the detection of grit in rubber pigments, in practically all of which it has been tacitly assumed that grit seriously impairs the quality of the pigment. Rubber articles, especially tire treads, made with pigments containing even small proportions of gritty material are considered inferior, and specifications covering grit are usually quite rigid. Pigment manufacturers have gone to great lengths to produce grit-free pigments, and the resulting product undoubtedly justifies the additional manufacturing care exercised. The importance of differentiating between actual grit and agglomerates of pigment particles which are subsequently dispersed during mixing operations has been pointed out by Murphy (Trans. Inst. Rubber Industry, 2, 100 (1926)), and various methods of accurately determining true grit have been suggested by this same author, by Gallie and Porritt (Trans. Inst. Rubber Industry, 2, 116 (1926)); by Esch (GummiZtg., 41, 82 (1926)), by Evers (Kautschuk, 1927, 70) and by others. The difficulty with which carbon black may be elutriated has limited the employment of such an agency in determining the proportion of grit present in it, and the laboratory has been confined to the use of screens of various size apertures for this purpose.
Some Properties of Carbon Black. I. Adsorption
Authors: Wiegand W. B. , Snyder J. W. 
Published: February 2011

Abstract
The diphenylguanidine (O. P. G.) adsorption test correlates well (0.8) with rubber-curing behavior in organically accelerated mixings, in respect to the broad classes of carbon black, but only moderately (0.4) in respect to standard rubber carbon black. The D. P. G. or similar adsorption test, although correlating better than the volatile-matter test, is therefore not capable of predicting with precision the rubber-compounding behavior of standard (rubber) carbon black. Carbon-black adsorption is much more marked in the alkaline than in the acid range. While heat-activated carbon blacks show marked increase in D. P. G. adsorption, heat-deactivated carbon blacks show greatly reduced alkaline and slightly increased acid adsorption, 2 which probably explains the anomalous iodine adsorption of heated blacks noted in the literature. In litharge compounds without added fatty acid, high-adsorption blacks spoil the cure by removing the fatty acid present in the rubber. Heat-deactivated carbon black leaves the cure relatively unaffected. In litharge compounds containing an excess of added fatty acid, however, both heat-deactivated and high-adsorption blacks improve the cure, doubtless through removal of excess acid. In general, for carbon black-litharge compounds a low-adsorption carbon black is preferable because it permits a minimum dosage of fatty acid.
Recovery of Rubber and Cotton from Uncured Tire Ply Scrap. Extraction Process
Authors: Powell Charles S. 
Published: February 2011

Abstract
A new method for reclaiming uncured tire ply scrap is described. This is an application of the familiar solvent-extraction process. It possesses several advantages over the other methods of separating the rubber and cotton fabric in the scrap, particularly from the standpoint of waste of materials, for both the cotton and the rubber are completely reclaimed without deterioration. If the process is to have wide application, however, means must be devised for utilizing the dilute rubber cement produced. THE utilization of tire trims has always been a difficult problem. Composed of uncured rubber and long staple cotton, their value is considerable. Certain quantities, after being broken down on a mill, can be used in bead covers, flaps, shoe soles, and mats without detrimental effects. The Dunlop Rubber Company (2) has been granted a patent covering a composition of uncured ply scrap, ground scrap, etc., to be used in the manufacture of objects of fibrous rubber.
Graphical Tensile-Testing Machine for Rubber Threads
Authors: Hahn S. H. , Dieterich E. O. 
Published: February 2011

Abstract
AMONG the many types of physical testing equipment which have been designed for or applied to the needs of the rubber industry, there has never appeared an entirely satisfactory graphical machine for performing tensile tests on small rubber samples, such as the threads and tapes used in making golf balls and elastic fabrics and cords. None of the common machines can be applied directly to the testing of single threads, and even tests on pieces of dumbbell shape are quite unsatisfactory, largely because the standard machines are comparatively insensitive at low elongations and tensions and also because they depend on the personal accuracy of an operator to observe several points along the stress-strain curve. The Schopper ring test is not entirely successful for tests on threads. Accordingly it appeared that such tests on light rubber threads could best be made on a curve-drawing machine, designed and constructed especially for the purpose. In many cases, the use of any other machine would have been impossible because frequent tests had to be run on single, cut threads from factory production and on samples taken from storage or from woven fabric.
The Determination of the Chloroform-Soluble Substance of Vulcanized Rubber
Authors: Minatani Iwasaburo , Aoe Ichiro 
Published: February 2011

Abstract
The determination of the chloroform-soluble substances in vulcanized rubber is a valuable clue to the content of certain ingredients, such as asphalt, mineral rubber, pitch, etc., for vulcanized rubber containing these ingredients shows a greater proportion of chloroform-soluble substance. Vulcanized rubber containing none of these materials generally has a chloroform extract of 0.3–3.0 per cent. It is generally high in uncured rubber, but even optimum and highly vulcanized rubber contains some chloroform-soluble substance. This fact was pointed out by Tuttle and Weber, in the Official method edited by the German Industrial Material Committee, and in a report of the Joint Rubber Insulation Committee (Ind. Eng. Chem., 9, 310; 6, 80). The object of the experiments was to determine the chemical nature of the chloroform-soluble substances in vulcanized rubber, as it is not known whether they are hydrocarbons or their derivatives, and whether they have the same composition at the different stages of vulcanization. As the chloroform-soluble substance in vulcanized rubber containing none of the softeners mentioned bove is obtainable only in small quantities, special attention was given in compounding of the rubber, and the following formula was used:
Isoprene and Rubber. Part 25. The Homologous Polymeric Hydrorubbers
Authors: Staudinger H. 
Published: February 2011

Abstract
Harries states in his studies on natural and artificial kinds of rubber “It would be of great importance to be able to carry out the reduction of rubber, because hydrorubber probably distills unchanged in a high vacuum, and therefore its constitution could be determined for certain.” This reduction was studied simultaneously by Pummerer and Burkard and by Staudinger and Fritschi. It is necessary to refer again to these works in order to correct earlier data on the basis of more recent experimental knowledge.
Value of Softeners in Tread Stock
Authors: DeFrance M. J. , Krantz W. J. 
Published: February 2011

Abstract
In view of these results, it may be concluded that in this tread stock the minimum amount of pine tar or mineral rubber commensurate with good factory processing is desirable if the maximum abrasion resistance for a given cost is to be obtained. This means that softeners which are effective, as such, in smaller amounts than those available at present should find a use in tread compounding. Stearic acid should be held to a ratio of approximately 4 parts per 100 of rubber. Most of the laboratory tests give indications in the same direction as the road wear, but none coincide exactly.
Influence of Physical Properties of Carbon Black on Its Tinting Strength
Authors: Kearsley E. P. W. , Roberts G. L. 
Published: February 2011

Abstract
1—Tinting strength is not an absolute function of particle. 2—No direct ratio exists between tinting strength and hiding power. 3—The thickness of the film of adsorbed gases on the carbon-black particles determines the tinting characteristics. 4—The volatile matter present and the oil-absorption properties serve as a measure of the relative thickness of such films. 5—The completeness with which these gases are displaced materially affects the tinting strength. 6—Complete displacement is only possible when the inter-facial tension produced by the dispersing medium at the surface of the carbon-black particle is sufficiently low to assure complete wetting.
Permeability of Rubber to Air. II: Effect of Stretch, Thickness, Milling, Compounding Ingredients, Kind of Crude Rubber, and Temperature of Vulcanization
Authors: Morris V. N. 
Published: February 2011

Abstract
The permeability of rubber membranes was found to be approximately inversely proportional to thickness. The recently developed “super” automobile inner tubes are therefore undoubtedly better air containers than the ordinary tubes of smaller gage. Most of the increase in permeability resulting from stretch can be accounted for by the decrease in thickness accompanying stretch. Pure-gum stocks made from various commonly used plantation rubbers did not vary much in permeability. A stock made from a wild rubber, caucho ball, had a somewhat lower permeability. Milling on a steam-heated mill was found not to change permeability appreciably. The early stages of milling on a cold mill reduced the permeability of a stock slightly. The temperature of vulcanization seemed to have no influence on permeability, provided the test slabs were cured to the same state. It may be concluded, therefore, that the recent trend towards higher temperatures of cure for inner tubes has not adversely affected their air-retaining capacities. None of the various softeners or other organic materials tried was found to effect any appreciable decrease in the permeability of a rubber stock The results indicate that permeability is roughly proportional to the volume of rubber hydrocarbon present in a stock. The nature of the principal compounding ingredient used in a stock does have some influence on permeability, however Clay, channel black, and blanc fixe are among the compounding ingredients having the most beneficial influence on permeability. Experiments with stocks containing various quantities of zinc oxide indicate that permeability varies inversely with the volume of pigment present. From the standpoint of the air-retaining capacity, the loading of inner-tube stocks with pigments is therefore desirable.
New Autographic Machine for Testing Tensile Properties of Rubber
Authors: Albertoni George J. 
Published: February 2011

Abstract
A description is given of a testing machine for the measurement of the tensile strength of materials having considerable deformation, such as rubber. A stress-strain recording device is described in which the strain recorded responds to the separation between a pair of independently movable pointers which may be made to follow the separation of two marks, spaced upon the sample before insertion in the machine. Mechanical means are also described to correct for variations in the test-piece cross section, and to produce equal chart displacements for equal angular deviations of the inclination balance.
Microturbidimeter for Determination of Rubber Content of Latex
Authors: Gehman S. D. , Ward J. S. 
Published: February 2011

Abstract
It is desirable to devise a method for determining the dry rubber content of latex which will be both more rapid than the two trial coagulation methods and more precise than the hydrometric method. The turbidity of latex, depending upon the volumetric number and size of the suspended rubber particles, offers a satisfactory criterion for the determination of the rubber content of latex. A microturbidimeter, herein described, has been adapted to such determinations. It permits more rapid determinations of the rubber content than the two trial coagulation methods. Its precision is less than the lengthy trial coagulation method, involving coagulation, creping, and drying, but is probably greater than that of the shortened trial coagulation method involving only coagulation and creping. Its precision is approximately 1 per cent rubber in 35 per cent latex. The turbidity of latex obeys the turbidity-dilution law for rubber-content values less than 15 per cent. The use of color filters, transmitting the shorter wave lengths of light, minimizes the effects of a difference in the effective mean particle size of different kinds of latex.
The Determination of the Size, Form, and Solvation of Macromolecules
Authors: Schulz Günter Viktor 
Published: February 2011

Abstract
As has been shown in earlier work, the molecular weight M of particles and the specific solvation volume s (the volume which corresponds to 1 gram of dissolved substance plus the solvent bound to it in the system) in a lyophilic colloid solution can be determined by means of osmotic measurements. This depends upon the fact that the osmotic pressure of such solutions is expressed by the equation: On the other hand, according to Eisenschitz, the relative viscosity of a suspension of elongated particles is represented by the equation: where l is the length, and d is the short axis of the particles. If it could be proved that the specific solvation volume s has the same value by the two methods of measurement, then the absolute dimensions of the particles in a colloidal solution could be obtained from parallel osmotic and viscosimetric measurements. This can now be done. On the assumption that newly dissolved rubber molecules are fiber molecules and the s values from osmotic and viscosimetric measurements are the same, all factors on the right side of equation (2) can be obtained from osmotic and roentgenographic data. Consequently the ηrel value can be calculated in advance. The values thus calculated agree extremely well with the experimental values of the relative viscosity.
Verification of the Specific Gravity of Rubber before and after Its Vulcanization
Authors: Kreps B. S. 
Published: February 2011

Abstract
1. Every hot vulcanization of a rubber compound leads to a volume decrease of the vulcanized material, or to an increase of its specific gravity. 2. The increase of the specific gravity of a rubber system depends directly on the condensation of rubber only, and does not depend on fillers. 3. The extent of the increase of the specific gravity of a vulcanized material is proportional to the quantity of rubber in the compound and to the degree of vulcanization. 4. Active fillers, as ZnO, and accelerators can influence the growth of the specific gravity of a vulcanized compound as agents promoting vulcanization; hence carbon black, contrary to Ditmar's opinion, can hardly contribute to condensation.
Roentgenographic Examination of μ-Polychloroprene (CH2:CClCH:CH2)x
Authors: Garbsch P. , Susich G. v. 
Published: February 2011

Abstract
μ-Polychloroprene (polymeric 2-chloro-1 ,3-butadiene or “Duprene”), recently described by Carothers, Williams, Coffins and Kirby, shows in the unstretched state an amorphous x-ray picture and when stretched a well-defined fiber diagram. Since a crystallization and parallel orientation of this kind upon stretching had not been observed previously in any natural or artificial product other than natural rubbers (smoked sheet, latex film, amorphous crepes), although some of these products may be highly elastic and may even split apart into fibers in the cold, the x-ray diagram makes possible a rapid and certain identification of the μ-polychloroprene.
Acetylene Polymers and Their Derivatives. III. The Addition of Hydrogen Chloride to Vinylacetylene
Authors: Carothers Wallace H. , Berchet Gerard J. , Collins Arnold M. 
Published: February 2011

Abstract
The results of experiments on the action of aqueous hydrogen chloride on vinylacetylene are described. The initial step consists In 1,4 addition and the primary product is chloro-4-butadiene-1,2, This readily undergoes isomerization, yielding chloroprene, which always constitutes a part of the reaction product. When cuprous chloride is present in the reaction mixture the isomerization proceeds more rapidly and no chloro-4-butadiene-1,2 is found in the reaction product. When sufficient hydrogen chloride is present the reaction proceeds further, yielding dichloro-2,4-butene-2.
Measuring Microscope for Rubber Specimens
Authors: Lofton R. E. 
Published: February 2011

Abstract
A microscope provided with a six-times micrometer eyepiece and objectives of 32 and 48 mm. focal length is suitable for measuring the cross-sectional dimensions of rubber test specimens. The width of specimens is usually greater than that of the die with which they were cut. The thickness of soft compounds as determined by the microscope is greater than that indicated by a gage of the plunger type. A MICROSCOPE of low power, equipped with a micrometer eyepiece, affords a convenient and practical means for accurately measuring the dimensions of rubber test specimens, and at the same time permits the inspection of specimens for defects. The equipment here described was designed particularly for measuring the width of the familiar dumb-bell shaped tensile test strips. At the present time no convenient and accurate gage is available for this purpose, and it is common practice to assume that the width of the specimen is the same as the die with which it was cut. The same equipment has been found satisfactory for determining the thickness of test strips, and is generally applicable for the measurement of dimensions up to about 6.4 mm. (0.25 inch). This use of the microscope embodies no original features. The method and equipment, however, are here described in some detail, since they may be of interest to investigators who may have occasion to make accurate mechanical measurements on rubber.
The Chemical Resistance of Rubber as an Engineering Material
Authors: Fritz H. E. , Hoover J. R. 
Published: February 2011

Abstract
Contrasting strangely with the liveliness exhibited in the physical reactions of rubber, we find in respect to chemical reactions a distinct lethargy, an inertia, which renders the material of unique value in certain engineering applications. It is apparent, when the manifold uses of rubber as a chemically resistant material are studied, that its value in the majority of cases depends not only upon the chemical inertia and peculiar physical properties of the basic substance, but also upon the fact that this basic substance has been intelligently combined with a variety of other materials. Too much emphasis cannot be placed upon the fact that rubber compounds are designed for specific uses; and that they can be bonded to many other structural materials with practically integral adhesion. This paper is a summary of data pertinent to the application of rubber compounds in resisting corrosion or avoiding contamination. Such data should be of service to engineers who are confronted with the selection of materials for uses where there are problems involving corrosion of equipment or contamination of product. While unvulcanized fine Para and pale crepe rubbers have been, and to a very limited extent are still, used as corrosion-resistant linings in chemical storage, process or transportation equipment, the great bulk of rubber applied to chemical service is vulcanized. The present discussion will be limited therefore to vulcanized rubber. When the conditions of service are accurately known by the manufacturer, vulcanized rubber can be compounded to resist actual immersion for long periods in any of the inorganic acids except those of strong oxidizing character. The same is true. of nearly all inorganic salts and alkalies, and to a somewhat more limited extent of commercial organic materials.
Atmospheric Cracks on Unstretched Rubber Products. Their Origin and Prevention
Authors: Merz Otto 
Published: February 2011

Abstract
It was proved that in collapsible boat material, in contrast to pure rubber mixtures: 1. Cracks occur without stretching, and 2. Cracking takes place sooner in sunlight than in the shade. Various possible ways are discussed for painting collapsible boat materials to protect them from cracking. The requisites for a serviceable paint are summarized. Waxes, rubber products, oil varnishes, and cellulose nitrate lacquers appear to be unsuitable because of various faults. Only combinations of paints of suitable composition meet these requirements. The poor resistance to weathering of collapsible boat materials can be overcome by immediately painting the new material.
The Influence of Temperature on the Evolution of Hydrogen Sulfide from Vulcanized Rubber
Authors: Cummings A. D. 
Published: February 2011

Abstract
This paper presents the results of measurements of the evolution of hydrogen sulfide from rubber-sulfur compounds heated at various temperatures. Determination of the amount of hydrogen sulfide produced under different conditions was used to measure the degree of decomposition of the rubber. Two types of experiments were carried out: (1) Samples of vulcanized rubber containing 8 to 32 per cent sulfur were heated for 8-hour intervals at 13 temperatures between 105° and 265° C., and (2) samples having sulfur contents of 4, 10, 18, and 32 per cent were maintained for about 200 hours at constant temperature, one set of specimens at 136° and another group at 220° C. These measurements of deterioration were undertaken in connection with an investigation on the electrical properties of vulcanized rubber at relatively high temperatures. During these experiments, samples of rubber-sulfur compounds had been subjected to a wide range of temperatures. Time of exposure to each temperature had been about eight hours. The purpose of the present work was to determine when the sulfur content of a specimen had changed sufficiently to affect its dielectric constant and power factor by a measurable amount. In order to approximate the conditions under which the electrical tests were made, it was necessary to determine the amount of decomposition when rubber vulcanized with 8 to 32 per cent sulfur was heated for successive intervals of eight hours each at temperatures changed in unequal steps from 105° to 265° C. To make this information more complete and to obtain additional data which could be compared with previous investigations, the work was extended to include determinations of the loss of hydrogen sulfide from vulcanized rubber heated for a long time at constant temperature. The electrical properties of the whole series of rubber-sulfur compounds is the subject of a separate investigation at this bureau, and will be reported in another paper.