bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of Variable-Temperature Cures
Authors: Sheppard J. R. , Wiegand W. B. 
Published: February 2011

Abstract
Employing the generally accepted empirical rule that intensity of curing action doubles with a rise of 15° F., relations are developed between the several variables of a cure segment with a constant temperature gradient—viz., “intensity of curing action,” “curing effect,” time, and temperature—and the constants of such a cure, initial temperature and temperature gradient. Exact evaluation of cures is extended to schedules involving variable temperatures by the equations showing curing effect as a function of the other properties of a cure. These are the equations of chief practical importance. Curing effect, the measure of the net value of a schedule in effecting vulcanization, may be determined for a given schedule either by calculation from one of the “effect” equations, by direct reading from one of the several herein displayed graphs of effect vs. other properties, or by estimation of the area under an intensity-time curve.
Abrasion Tests of Rubber Stocks Containing Various Types of Carbon Black
Authors: Plummer W. B. , Beaver D. J. 
Published: February 2011

Abstract
With respect to the results noted herein an the relation of abrasion loss to size of abrasive material, it is regretted that as yet no results have been obtained which cast much light on the reasons for the break in the curves of Figure 1. It is possible, if not probable, that the unexpected phenomena whose existence is indicated by these results may be responsible for the commonly observed discrepancies between laboratory abrasion tests and road tests. It is hoped that further studies may give more useful information on this relation. The abrasion results on aged stocks present several important points. It is, of course, obvious and fully realized that abrasion in use takes place only on the surface layer of a tire tread, but attention has not before been called to the very considerable effect which the aging characteristics of the carbon black used in the stock may have on the abrasion resistance of this surface layer. The present results show that, with two stocks differing only in their carbon black content, the relative abrasion resistance of the surface layers after aging may be in reversed ratio to those of the unaged stocks. This evidently will be a decisive factor in the relative useful life of the tread if the rate of surface aging is greater than the rate of tread wear. Surface conditions or, in other words, the time of storage before use, the daily mileage, existing road and climatic conditions, etc., will determine this relation.
Carbon Blacks and Their Use in Rubber. III—Aging Effects
Authors: Cox L. B. , Park C. R. 
Published: February 2011

Abstract
The aging properties of compounded rubber stocks are affected by the carbon black which is used. The order of increasing superiority for the blacks tried is Super Spectra, Micronex, Charlton, Goodwin, and Thermatomic. The order of increasing superiority of accelerators is diphenylguanidine, hexamethylenetetramine, ethylidene-aniline, mercaptobenzothiazole. The last two are put in this order mainly because of the inferior original properties of ethylidene-aniline. Results of tensile, abrasion, and weight increase tests are in reasonably good agreement. The effect of acidity in any compounding material is neutralized in a stock containing zinc oxide. Stearic acid is without effect upon aging properties of cured rubber.
Softeners and Anti-softeners
Authors: Zimmerman Erle C. , Cooper Leslie V. 
Published: February 2011

Abstract
In the manufacture of rubber goods various materials are incorporated with the rubber in order to produce a mixture that will process more easily. Such materials are usually called fluxes or softeners. A simple method of determining the relative effects of such materials is described. This consists in mixing the material in rubber under standardized conditions and determining the plasticity of the product by the Williams method. Some materials show stiffening instead of softening action and both types are shown in the results reported in this paper. Benzidine and p-amidophenol are examples of materials which stiffen rubber. MANY materials used in the compounding of rubber exert an influence on the plasticity. Usually a material is specifically added to increase the plasticity and is called a softener, but in some cases the effect on plasticity is purely incidental to some more important function, such as acceleration or protection against deterioration on aging. The effect of this class of materials may be towards either a more or a less plastic mix; in the latter case it is correct to class the material as an antisoftener.
Reënforcement of Rubber by Fillers
Authors: Blake John T. 
Published: February 2011

Abstract
Wiegand's “Δ A” function, as represented by the double integral of tensile with respect to elongation and volume of a pigment over the base mix, is a practical means of expressing the reënforcing effect of the filler. On the other hand, the volume range over which the bonding of the filler is greater than the strength of the rubber matrix gives a better understanding of the condition of the filler in the rubber. Apparently, the importance of fatty acids and other polar compounds in dispersions can be put on a sound theoretical basis.
Determination of Sulfur in Rubber by the Perchloric Acid Method
Authors: Wolesensky Edward 
Published: February 2011

Abstract
In a search for a rapid and accurate method for determining sulfur in rubber it was found that oxidation of the sample by means of sodium peroxide in the Parr bomb is unsatisfactory when the sulfur content of the rubber is low because the samples that can be used for this purpose are too small for accurate results, or, if larger samples are used, the oxidation is incomplete. The use of a mixture of nitric and perchloric acids, as described by Kahane, is also unsatisfactory; but with certain modifications the method may be made to yield very good results, and if fusions are unnecessary, it will save time and labor. The chief modifications recommended are the use of a more dilute solution of nitric acid (equal volumes of the concentrated acid and water), allowing the rubber to dissolve completely on the steam bath before heating more strongly, then heating to gentle boiling until oxidation is complete, and finally destroying the residual nitric acid by means of hydrochloric acid. The use of a larger flask (500 to 800 cc.) is also recommended, and suggestions are also made for the adaptation of this method to the analysis of those rubber compounds which contain barium, lead, etc.
Inaccuracies in Determination of Acidity of Raw Rubber by Water Extraction
Authors: Cummings A. D. , Simmons H. E. 
Published: February 2011

Abstract
From the results obtained it is concluded that the boiling water hydrolyzes some of the esters in the acetone extract. In the case of direct extraction of the rubber with water, hydrolysis of esters must take place in the rubber, forming water-soluble acids; or else, although the esters are practically insoluble in the water, it extracts a little ester each time the extraction thimble empties (Bailey-Walker apparatus), carrying the ester down to be hydrolyzed in the boiling water below. Temperature and time of heating play a prominent part. The temperature must be close to the boiling point and the acidity increases progressively with time of heating. The fact that temperature is so important in producing this effect accounts for the erratic values obtained by direct water extraction. On the electric hot plates used water did not always boil steadily, and that contained in the thimble might vary considerably in temperature, much of the time not being hot enough to hydrolyze or extract any ester. Therefore, to avoid any difficulty in the determination of water-soluble acids in rubber, extract first with acetone, then digest this extract with water on a boiling water bath until no increase in acidity of the water extract is obtained. This is a part of the procedure developed at the Netherlands Government Institute by Van Rossem and Dekker.
Effect of Repeated Reclaiming of Rubber
Authors: Miller George W. 
Published: February 2011

Abstract
1—Reclaimed rubber, without the addition of new rubber in a subsequent vulcanization, cannot be repeatedly cured and reclaimed without a considerable deterioration in its physical properties. 2—The rubber scrap for reclaiming should be intelligently blended, and an endeavor made to keep the concentration of once-reclaimed rubber as low as is economically possible. 3—The chloroform extract and sulfur analyses of the uncured reclaimed rubber yield valuable information in regard to the quality of the product.
Principles of Patent Law Involved in the Weiss Patent Litigation
Authors: Deller Anthony William 
Published: February 2011

Abstract
OWING to the widespread interest in the chemical industry generally, and especially in the rubber industry, in diphenylguanidine as an accelerator in the vulcanization of rubber, it is believed that a discussion of the recent decision of the Supreme Court of the United States in the matter of the Weiss diphenylguanidine patent will serve a dual function of informing chemists about the status and the history of the Weiss patent and, at the same time, of expounding some of the principles of patent law involved in the case.
Color Reactions of Rubber and Gutta-Percha
Authors: Kirchhof F. 
Published: February 2011

Abstract
THE present paper was suggested by a recent publication of Pauly on the same subject, who applied the well known sterol reactions of Hesse, Liebermann, Tschugajeff, etc., to the hydrocarbons of rubber and gutta-percha. These reactions depend either upon the action of concentrated H2SO4 on chloroform solutions of the substances in the presence or absence of acetic anhydride (Liebermann, Burchard and Hesse reactions) or other solvents, or condensation reagents are used, such as acetyl chloride and zinc chloride by Tschugajeff, and acetic acid with arsenic trichloride by Kahlenberg, and trichloroacetic acid with a trace of formaldehyde by Godoletz. All the known sterol reactions take place also with rubber or gutta-percha, with the appearance of intense red or violet colorations of varying stability, the color depending in part upon the quality and in part upon the purity of the samples. The Burchard reaction in particular is very sensitive in these respects. Thus with rubber purified with alkali by the Pummerer method, the color is a Bordeaux red which does not change for a long time, whereas solutions of unpurified rubber change rapidly, a change which is rightly ascribed by Pauly to relatively rapid oxidation in the presence of oxidation products in the case of the unpurified rubber.
Some New Laboratory Work on Rubber
Authors: Somerville A. A. , Ball J. M. 
Published: February 2011

Abstract
CRUDE rubber is not of much use commercially or industrially until after it has been put through a chemical process discovered by Charles Goodyear: that of adding sulphur and heating. But sulphur is not the only material that can be used to change and improve the natural physical properties of raw rubber. There are other things than sulphur that are beneficial, one of which is Selenium. It is a pleasure to be permitted to talk here in Boston before a meeting of the Northeastern Section of the American Chemical Society and the Boston Rubber Group, devoted at this time particularly to the subject of rubber. It is a privilege to be permitted to talk on the subject of Selenium at this meeting because it is coming back very close to the home of Selenium so far as it is associated with the rubber industry.
The Mechanism of the Reinforcement of Rubber by Pigments
Authors: Depew Harlan A. 
Published: February 2011

Abstract
Dispersed pigment reinforces by increasing the tear resistance. Flocculated pigment hardens rubber and reinforces by increasing the resistance to cutting. It may also increase the tear resistance, but not to as great an extent as if the pigment were well wet. The mechanism of the reinforcement by increasing tear resistance is that the pigment particles act as obstacles that cause the tear to proceed in a longer path going around the particles. Due to the round-about path, the component of the force in the direction of the tear may be small. Accordingly, it is possible in the case of a fine pigment to increase the tear resistance even though the rubber-pigment bond is much weaker than the rubber itself. The hardness of a stock containing flocculated pigment is due to the rigidity of the structure assumed by the flocculated pigment. During the early moments of hot vulcanisation, rubber is semifluid and the degree of dispersion may be largely determined during this period; some of the pigments becoming dispersed and some becoming flocculated. Flocculated pigment and large particles introduce uneven stresses during the straining of rubber that lower the reinforcement below what might be expected.
The Evaluation of Carbon Blacks
Authors: Cranor D. F. , Braendle H. A. 
Published: February 2011

Abstract
In conclusion, it is shown that the “Delta A function” provides an instrument for the classification of carbon blacks as regards their usefulness to the rubber compounder. It is an index of widely inclusive character and not only indicates performance at optimum concentration, but also the range of effectiveness. The writers have undertaken exposition of the special applications of this to the classification of carbon pigments, pointing out the precautions necessary for its accurate use. We believe it important to supplement the “Delta A function” with other stress-strain data, also with laboratory performance tests, and finally with service records, when it is necessary to differentiate between carbons of the same general category. On the other hand, we believe no study of carbons or other pigments is complete unless “Delta A” values are included. Acknowledgment is gratefully made for the valuable suggestions of W. B. Wiegand and also the cooperation of Binney & Smith Co., who supplied all of the carbon blacks investigated and gave permission to publish the data covered by this paper.
Technical Application of Antioxidants
Authors: Bridgwater E. R. 
Published: February 2011

Abstract
IT is unfortunate that the process of vulcanization, to which the commercial use of rubber is almost wholly due, makes it much more susceptible to oxidation. The deterioration that sets in as soon as rubber is vulcanized was first attributed to oxidation by Miller in 1865 but it is only during the last 20 years that a serious effort has been made to find means of preventing it. During this period it has been found that many chemicals retard the oxidation of rubber when incorporated with it prior to vulcanization. Phenolic compounds, primary and secondary amines, aminophenols and condensation products of aldehydes with amines are the chemical groups within which the most valuable antioxidants are found. Many amines and aldehydeamine condensation products are also vulcanization accelerators and some of the earliest known accelerators have a mild antioxidant effect. Para-phenylenediamine and para-aminodimethylaniline were used as accelerators long before the term antioxidant was coined and their favorable effect on the aging properties of rubber compounds has been a matter of common knowledge for more than ten years. Recent investigations have disclosed numerous compounds in these classes that have little or no accelerating effect and are far more effective in retarding oxidation than any of the known accelerators.
Goodyear Experience in Temperature Control of Mill Rolls
Authors: Moorhouse R. W. 
Published: February 2011

Abstract
IT is well known that in milling a batch of rubber or compounded stock, the temperature of the mill rolls rises—rapidly at first, then more slowly—to a given temperature at the end of the run. There are, however, a number of factors which affect in varying degree not only the temperature eventually reached, but the intermediate temperature of the roll surfaces. Of these we may form two groups, those tending to increase and those tending to decrease the temperature. Factors Affecting Roll Temperature Initially high temperature of batch, toughness of the rubber or stock, heavy loading, large bank and gage and increasing ratios of roll speeds, tend to increase the temperature. Merely starting the average cold rubber through the mill increases the roll temperature 15° F. in the first five minutes, while using hot stocks increases this to 20° F. in two minutes. Toughness of stock affects roll temperature by varying the amount of heat produced in the first few minutes of milling, the rise of temperature increasing with the tougher stock. Doubling the gage of the mill increases the roll temperature 10° F., due to increased working of the batch. The same effect is obtained by increasing the size of the batch, up to the point of producing an idle bank. As small a change of ratio as from 1.11 to 1.17 will produce a rise of 10–12° F. in roll temperature. Cooling may be obtained, but only momentarily, by the addition of cold compound or a little water to the stock on the mill.
Contribution to the Thermochemistry of Rubber
Authors: Boström Siegfried 
Published: February 2011

Abstract
1. An apparatus is described suitable for the calorimetry of slow reactions. 2. By determining the heat of adhesion between fillers and rubber when mixed together, a method is found for the relative evaluation of technical rubber fillers. The utility of the method is shown by the comparison of the thermal data obtained using several types of black with physical data already published. 3. The elongation and contraction of raw rubber were studied from a thermodynamic standpoint, and also the change in total energy, the work of elongation, and its temperature coefficients. 4. The heat tone of the reaction between sulfur chloride and rubber dissolved in benzine was determined at a concentration of 0 to 1.3 g. of sulfur chloride to one gram of rubber. Heat tones depending on chemical and colloid-chemical processes may be exhaustively studied in this way.
Making Rubber Goods of Latex by Electro-Deposition
Authors: Klein Paul 
Published: February 2011

Abstract
Present manufacturing methods are characterized by repeatedly plastifying the rubber, partly by mastication and partly by heating. These operations involve the use of heavy machinery, and furthermore in certain cases the rubber mixes are then dissolved in organic solvents, a procedure which has the additional drawback of a more or less considerable loss of organic solvents. The question at once arises: why should these many difficult and expensive steps be necessary in order to prepare a shaped body containing all the compounding and other ingredients from the original latex? There is only one answer to this question, and that is, the actual rubber manufacturer does not start with the liquid sap. Obviously it should be much easier to handle a liquid, to add to it the desired dispersed ingredients, and then to use it in some way or another to obtain the shaped article instead of performing all the masticating operations which are carried out with so much power and such heavy and expensive machinery. But not only is this an economic question. There is more involved. The mastication of the rubber impairs its quality, and the longer the mastication of a certain mix, the poorer the physical properties of the product obtained therefrom will be.
Rubber Structure Research and Its Bearing on the Elastic Properties of Colloids in General
Authors: Hauser E. A. 
Published: February 2011

Abstract
The least, therefore, to which in my opinion the colloid chemist or colloid physicist may lay claim is credit, not only for a fair contribution to the structure of rubber, but for more than that—for having laid the foundation of an entirely new conception of fibrous and elastic matter in general; this with the aid of a method, x-ray analysis, which has been so severely criticized in its connection with colloidal research. I have purposely said “foundation,” because considerably more work will have to be done, and a final conception will not be generally accepted until we have learned to correlate this finding with results still to be obtained in a study of double-refraction phenomena and possibly when we have learned more in regard to the interpretation of results obtained when using light of intermediate wave lengths. There is, however, nothing which should discourage us and our slogan for the purpose of increasing progress should be at all times—keep going—and how?
A New Physical Test for Vulcanized Rubber
Authors: Wright D. D. 
Published: February 2011

Abstract
This test, by use of a sample of new design, subjects rubber to a combination of tensile and shearing stresses. Shear, however, is the predominating stress. Certain aged inner tubes have been found which deteriorated more when examined by this test than a comparison of their tensile-stress-strain curves with those of fresh tubes would indicate. Tearing action seems to be approximated by this test. The effect of overcure in some cases has been recorded at earlier stages by this test than by the tensile criterion. The test is easy to perform and with usual precautions should have an accuracy of approximately 10 per cent. VULCANIZED rubber is frequently required to withstand, not only the simple stresses such as those of compression, tensile, and shear, but also the combined effects such as torsion, tearing, bending, etc. It has been observed that, as some vulcanized rubber samples age, their resistance to shearing and tearing stresses decreases much faster than their resistance to tensile stresses, as determined under the standard procedure of rubber-testing.
Diffusion of Water through Rubber
Authors: Schumacher Earle E. , Ferguson Lawrence 
Published: February 2011

Abstract
The diffusion of water through thirteen rubbers of different compositions has been measured. The data obtained by two different methods are in satisfactory agreement. The mathematical derivation of a simple formula for calculating the rate of diffusion has been given. The diffusion measurements have shown: (a) that the rate of diffusion of water through a rubber membrane is inversely proportional to the square of the thickness; (b) that the rate of diffusion decreases greatly with increase in hardness; (c) that the effect of saturating the rubber with water is to increase the rate of diffusion through it, due probably not only to an increase in the water vapor pressure within the rubber, but also to a decrease in hardness; (d) that there is no intimate relationship between rate of diffusion and minor variations in the composition of the rubber.
The Oxidation of Vulcanized Rubber
Authors: Van Rossem A. , Dekker P. 
Published: February 2011

Abstract
SINCE Kirchhof in June, 1927, gave to the first general meeting of the German Rubber Society in Essen a detailed review of work concerned with the oxidation of rubber, it seems superfluous to publish any extensive bibliography thereon. We prefer to limit ourselves, for the present, almost exclusively to a few experiments in this field. However, we may refer in a general way to the work of others. It is a notable fact that all investigations of the oxidation of vulcanized rubber have been always based on the kinetics of the oxygen combination, and, as far as isolation of the oxidation products is concerned, on a late stage of oxidation, the isolation of oxidation products during the early stages of oxidation being left out of consideration. Thus, for example, Kirchhof in his work published in 1913 studied the behavior of ground vulcanized rubber which had been heated for 100 hours in a current of air at 100° C. and thereby strongly oxidized, as indicated by the increase in weight (11–13%). Eaton and Day later in 1919 made experiments of a similar nature. Here, too, the kinetics principally were studied, and the samples were examined only after oxidation was far advanced. Again in Kirchhof's recent work already mentioned, the oxidation products were studied only after prolonged oxidation.