bluuebunny/crossref_metadata_2025_split huggingface dataset:
Conversion of Rubber into Thermoplastic Products with Properties Similar to Gutta-Percha, Balata, and Shellac. II—Chemistry of the Reaction
Authors: Fisher Harry L. , McColm Eugene M. 
Published: February 2011

Abstract
The shellac-like products formed by the action of organic sulfonic acids on rubber have been studied chiefly. After purification the chief constituent is found to be a hydrocarbon with the same empirical formula as that of rubber, C5H8, and it is 55 to 60 per cent as unsaturated as the rubber hydrocarbon. Addition products of hydrogen chloride and hydrogen bromide have been prepared. Vulcanization with sulfur gives a maximum combined-sulfur content of about 21 per cent, corresponding to 57 per cent unsaturation as compared with rubber. Oxidation, hydrogenation, bromination, nitration, etc., have also been studied. The purified hydrocarbon is white and is completely soluble in the rubber solvents and insoluble in alcohol, acetone, etc. It is much more stable toward heat than rubber. The gutta-percha and balata types are only partially soluble, but analyses, yields, etc., indicate that they consist of similar isomeric hydrocarbons.
Methods for the Purification of Rubber Hydrocarbons
Authors: Pummerer Rudolf , Miedel Hermann 
Published: February 2011

Abstract
The various methods which have been used for preparing the rubber hydrocarbon in a pure state are discussed critically. The authors show that Harries' method of acetone extraction and precipitation of the rubber from benzene solution gives a product which still contains a small proportion of protein and sugars. Fractional precipitation gives a better product, but it is not entirely free from nitrogen. Purification with methyl alcoholic potash removes all the nitrogen, but the last traces of the alkali are difficult to remove. The diffusion method is then described. This gives an analytically pure rubber hydrocarbon. In scientific investigations of rubber, many research workers have heretofore given too little attention to the obvious problem of isolating in a pure state the rubber hydrocarbon, or perhaps the several hydrocarbons in the natural raw product: It is timely to gather together and evaluate the various methods useful for this purpose.
Effect of High vs. Low Sulfur in Vulcanizing Reclaim
Authors: Cartlidge R. E. , Snyder H. L. 
Published: February 2011

Abstract
To obtain the optimum results in curing compounded stocks containing whole tire reclaim, a minimum of 2.0 and a maximum of 2.5 per cent sulfur are required. This range of sulfur content, based on the total weight of reclaim in the compound besides the 4 per cent added for curing the crude rubber present, gives the flattest and longest curing range in conjunction with the highest physical qualities. Three per cent of sulfur on the straight reclaim-sulfur mix gives the maximum physical properties.
The Mercury Vapor Arc Lamp: Its Uses in a Rubber Factory
Authors: Nagle P. G. 
Published: February 2011

Abstract
Ultra-violet light has recently been brought very prominently into public notice owing to its successful application by the medical profession to the cures of various ailments, and skin diseases in particular; there are, however, many possibilities of its increased application to various industries. First noticed some 200 years ago, actinic rays were found to produce certain chemical changes in many substances, particularly silver salts; and the artificial production of light containing these rays became a matter of some little importance. Earlier sources for their production were burning magnesium, incandescent calcium oxides, the electric arc between carbon poles, the iron arc, tungsten arc, aluminium and silica arc, etc. In 1901 a mercury vapor lamp was produced, depending upon the formation of an arc between two columns of mercury in an exhausted glass tube. This lamp, while giving a certain amount of ultra-violet light, lost much of its actinic value owing to the absorption of the greater part of these rays by the glass of the tube, and the main use of the lamp was as a convenient source of monochromatic green light. The substitution of a quartz tube for glass was found to allow a vastly greater amount of ultra-violet light to be transmitted. A great improvement has since been obtained by the production of a lamp giving an arc between mercury columns at ordinary atmospheric pressure. Such a lamp was used in obtaining information which is incorporated in this paper; the actual lamp being a Kelvin Bottomley and Baird “fugitometer,” working at 460 volts d. c. The spectrum given by mercury vapor is dependent upon the temperature and nature of the arc, and this must be borne in mind in any attempt at comparative results where different lamps have been used.
Factors in Supply and Use of Cooling Water
Authors: Shoaff Paul S. 
Published: February 2011

Abstract
WE OF the rubber industry are naturally interested in water mainly as a cooling agent. We are concerned with its source, the quantities regularly available and the temperature at which it is supplied. A reference to the requirements of the Goodyear factories in Akron indicates how important a factor it is. The two plants must be supplied with over 20,000,000 gallons of water per day exclusive of the amount taken from the city mains for special purposes. Approximately 13,250,000 gallons of this volume are used for cooling mills, internal mixers, calendars and tubing machines. The greater proportion of this is recovered and with the addition of fresh water is employed for cooling heaters, in the reclaiming plant and for various services throughout the factories. When the day's cycle has been completed, more than 13,000,000 gallons of warm water are returned to their principal source, the Little Cuyahoga River. In the cooler seasons all of the 13,250,000 gallons of cooling water come from the impounded waters of the river, which is fed largely by Wingfoot Lake and partly by Springfield Lake. During the summer the daily supply is a mixture of deep well water and the necessary balance from the river.
Effect of Various Types of Carbon Black on Certain Physical Properties of Rubber Compounds
Authors: Beaver D. J. , Keller T. P. 
Published: February 2011

Abstract
The data presented herein show that in general the presence of oxygen on carbon black retards the rate of vulcanization in direct proportion to the amount of oxygen present and also decreases the maximum physical properties obtainable with a given amount of accelerator. The aging data show that the presence of this oxygen on the black increases the rate of aging as the amount of oxygen increases, but not in direct proportion to the per cent of this oxygen present. It can be concluded, therefore, that compounds which contain a small amount of oxygen, such as thermatomic, G black, or acetylene black, will give better aging stocks than compounds containing higher amounts of oxygen such as lampblack and standard channel blacks. No correlation could be found between the acetone extract, iodine adsorption, or oil adsorption, and the effect of these blacks on the rate of cure or aging.
The Isomerization of Rubber to Cyclorubber under the Influence of High Tension Alternating Currents
Authors: Fromandi Guido 
Published: February 2011

Abstract
Chemical transformations by means of high tension alternating currents, accompanied by the activation of oxygen were investigated extensively toward the end of the last century by de Hemptinne, who studied the behavior of a large number of chemical substances and systems under the influence of these discharges. These transformations are in general characterized by the fact that the discharge causes deep seated changes in the molecular structure of the substances, principally organic, on which it acts. The chemistry of some, indeed most, of the reactions produced by the silent electric discharge in liquid and solid systems has never been definitely explained, particularly when these reactions are accompanied by a complete destruction of the molecule. In the so-called “Voltol” oil process, the oil becomes more viscous when treated by the silent discharge and becomes a valuable lubricant, well known in the automotive market today. This product led to a thoróugh knowledge of the process and to a confirmation of Nernst's theory, according to which the increase in viscosity is due to a displacement of the intramolecular bonds caused by the impact of ions and electrons, resulting in the formation of polymerization products of high molecular weight. The discharge is produced in a rarified atmosphere of hydrogen, and due to the alternating field the ions and electrons in the gaseous layer undergo such acceleration that they increase markedly in numbers by impact. Because of their great kinetic energy the effect on the liquid molecules is exceptionally violent. The molecules split off hydrogen, which, because of its atomic, highly active form immediately becomes attached to the unsaturated bonds, forming saturated compounds. This is true of saturated as well as unsaturated compounds used as the substances to be treated, the mechanism of the reaction being characterized by the following general equation:
Some Observations with Ultra-Accelerators
Authors: Cummings A. D. , Simmons H. E. 
Published: February 2011

Abstract
ALTHOUGH much has been done on accelerators, in such a vast field there is always room for additional work, particularly if, as Whitby predicts, ultra-accelerators will be the main class used in course of time. This investigation was started with the following points in view: (1) to prepare several thiuramdisulfides and related compounds; (2) to note their relative behavior when used as accelerators; and, if possible, deduce some explanation for the mode of action of the class or for the behavior of some particular compound, or gain additional evidence for any existing theories. The relative inactivity of thiurams derived from primary amines has been mentioned but no explanation published. Evidence is presented to show that decomposition of the compound into hydrogen sulfide and a mustard oil takes place so quickly at the temperatures used that there is not time for the generation of much active accelerator. It was found that tetramethylthiurammonosulfide plus sulfur equivalent to the difference in sulfur content between it and the disulfide gave a cure in a rubber-zinc oxide mix practically equivalent to that given by the disulfide alone. This indicates that zinc dimethyldithiocarbamate may be the active accelerating agent.
Organic Rubber Colors
Authors: Naunton W. J. S. 
Published: February 2011

Abstract
DYESTUFFS are divided into about twelve main groups according to their method of manufacture; thus we have the sulfur colors, which are made by fusing together various organic compounds with sulfur and sodium sulfide, the azo colors in which the intermediates are coupled together by means of the diazo reaction, and so on. Most of the organic dyestuffs may be regarded as salts in which either the colored organic base is combined with a colorless inorganic acid (basic dyes) or the colored organic acid is combined with a colorless inorganic base (acid dyes). This salt formation has in most cases rendered the color soluble in water. In the absence of salt-forming groups in the colored compounds, or when their action is insufficiently potent, the resulting substances are sufficiently insoluble in water to be of direct use in the rubber industry; examples of such pigments are monolite yellow and monolite red. A consideration will be made of the method of employing the water soluble dye-stuffs, which are far more numerous than the insoluble ones, in the coloring of rubber. The obvious way is to convert them where possible into lakes or insoluble colored compounds. The two most important processes of lake making are (1) precipitating an insoluble salt of the soluble dyestuff upon a suitable white pigment, known as the “lake-base” and (2) employing a mineral earth which absorbs certain dyes from aqueous solution.
Rubber as it is Revealed by X-Rays
Authors: Clark George L. 
Published: February 2011

Abstract
THE beginning of the year of 1929 seems to be a logical time for considering critically the status of knowledge concerning the fundamental structure of rubber. Of all the contributions by various methods to the problem, those which have come as a result of the application of X-ray diffraction methods may be considered the most unique and perhaps most important in the past few years. It was known previous to 1925 that when rubber is strongly stretched it becomes warm, its specific gravity increases and it becomes doubly refracting. The name of J. R. Katz has become renowned throughout the world as a result of the experiment which he performed of causing a fine beam of X-rays to pass through a specimen of stretched rubber behind which was placed a photographic film. This experiment was one of those fortunate accidents which appear frequently in the history of science, but on the other hand, it was the result of clear thinking, rational deduction, and a keen appreciation of the possibilities of application of X-rays to the examination of the ultimate structure of materials.
Measuring Temperatures of Calender Rolls
Authors: Keltner L. R. 
Published: February 2011

Abstract
IT has only been within recent years that the importance of knowing the exact conditions under which rubber is processed has been appreciated. This is especially true of the calendering operation. For many years a calender man's experience was the only assurance one had of producing properly processed material. Demand for greater uniformity of product now necessitates more uniformly processed materials. The ultimate outcome of these demands was the setting up of a definite set of mixing and calendering specifications. It is readily recognized that a calendering specification would not be complete without some reference to the calender roll temperature. The effect of heat on rubber processing cannot be discussed here but it should be stated that it is of tremendous importance. The need for a roll temperature measuring device thus presented itself and various types of instruments have been experimented with. Early experiments were made in a crude manner by attaching the hot junction of a thermo-couple to a small 1-inch square brass plate which was mounted on a yard stick. This stick was used as a lever and a cross bar from the calender housing as a fulcrum. After the brass plate had been placed at the desired spot on the roll, pressure was applied by pulling up on the end of the stick opposite the junction. Data obtained were satisfactory but the apparatus. had no practical application in production. Other experiments along the same line were carried out later.
X-Ray Contributions to the Problem of Polymerization
Authors: Clark George L. 
Published: February 2011

Abstract
It may be readily admitted that x-ray studies of the problem of polymerization are only in their beginning. Some complexities—as, for example, small unit cell dimensions— have been added, but in general a real contribution has already been made as a basis for further advances, which will come as knowledge of interpretation increases and as experimental technic improves.
Report of the Raw Rubber Specifications Committee
Authors: Spear Ellwood B. , Boggs C. R. , Simmons H. E. , Trumbull H. L. , Shepard N. A. 
Published: February 2011

Abstract
AS INTIMATED in a previous report of the Committee presented at the St. Louis meeting in April, 1928, a temporary procedure was adopted in order to ascertain whether or not the five laboratories represented on the Committee could obtain reasonably comparable stress-strain relationships using the same batch of rubber. A complete report is appended in which the procedure is outlined and the results of each laboratory are given in considerable detail. After careful deliberations the Committee has concluded that the testing of raw rubber is not in a very satisfactory state. It therefore makes the following recommendations: (1) The testing of raw rubber should be made the subject of thorough investigations. (2) The work should be undertaken by a Physical Testing Committee, preferably under the jurisdiction of the Rubber Division of the American Chemical Society.
Some Practical Aspects of Rubber Evaluation
Authors: Dinsmore R. P. 
Published: February 2011

Abstract
In various papers, published in the past three years, E. C. Zimmerman and the writer have made references to the variability of crude rubber as determined by the properties of vulcanized compounds of various types. We were, I believe, the first to point out the chief stumbling block in the way of establishing a standard test formula for evaluating crude rubber, namely the variation in both quality and rate of cure produced by curing the same rubber with different curing agents. At the outset we were confronted with difficulties which resulted from a deplorable lack of standardization of rubber testing methods, and more specifically from a lack of agreement as to the proper way to select comparable cures. Indeed, it is obvious that these drawbacks have been among the major causes for lack of correlation of available data on the subject. We have stressed the importance of considering those properties of the vulcanizate which are reflected in the performance of the finished product, and have stated our objections to many of the popular criteria, such as “slope,” tensile product, tensile, and coefficient of vulcanization. We had concluded that aging should be the chief criterion of best technical cure. Accelerated age tests cannot be relied upon for comparison of different mixes, but experience has shown that for lightly loaded mixes hand tear is a reliable method of fixing the best aging cure. With this as a means of selecting the time of cure, the quality was studied by comparing the stiffness of the stress-strain curve at best cure. Later, in a paper on acceleration classification, if was shown that these conclusions might properly be modified when dealing with loaded mixes. Here the cures, as selected by hand tear and by maximum, tensile product, were in substantial agreement, except in the case of non-accelerated stocks.
The Nature of Vulcanization Part IV
Authors: Stevens H. P. , Stevens W. H. 
Published: February 2011

Abstract
(1) At low temperatures by means of accelerators it is possible to produce vulcanites containing “combined sulfur” considerably in excess of that required for the formula C5H8S. Such vulcanites may be obtained by vulcanizing at 100° with a variety of ultra-accelerators with and without zinc oxide as an activator. If zinc oxide or a zinc salt is used the excess coefficient cannot be explained by the presence of the zinc sulfide in the vulcanite. (2) The amount of sulfur combined with the rubber, given sufficient heating and presence of accelerator, is mainly dependent on the excess of sulfur present. (3) Extraction of the vulcanite with hydrochloric acid-ether mixture removes a part of the “combined” sulfur. A considerable amount is removed when the amount of combined sulfur is very large, but even then the amount of sulfur remaining is considerably in excess of that required by the formula C5H8S. (4) Vulcanization at low temperatures in solution in accordance with Whitby's procedure with the aid of accelerators also yields vulcanites with coefficients in excess of that required for the formula C5H8S. (5) The result of vulcanization at low temperatures is approximately the same, whether the rubber contains all the protein and serum ingredients, the usual proportion, or very little. (6) Extraction of sulfur from vulcanite with hot acetone vapor is not complete after 1210 hrs. (7) Having regard to the hydrogen sulfide and other volatile sulfur compounds evolved in appreciable quantities during vulcanization, it is evident that part of the combined sulfur results from substitution of hydrogen by sulfur. This substituted product is decomposed by the hydrochloric acid-ether mixture. It may not be possible to decompose the whole in this manner. Consequently, any “combined” sulfur in excess of that required by the formula C5H8S may result from substitution in the molecule.
Effect of Antioxidants in Typical Rubber Stocks
Authors: Reed Marion C. 
Published: February 2011

Abstract
The results of these tests show that antioxidants are of value in stocks which become hot in service, such as bus tubes, belt frictions, and heavy truck tire treads. It is believed that aging at 90° C., both in air and in an inert gas free from oxygen, will be of assistance in separating the factors of oxidation and overcure in designing rubber compounds for resistance to heat.
A New Flexing Machine for Rubber
Authors: Torrance Philip M. , Peterson Lester C. 
Published: February 2011

Abstract
TREAD cracking is one of the most annoying problems occupying the attention of rubber chemists at the present time. While there is no doubt that tread design and the construction of the tire as a whole have great influence in producing this phenomenon, the nature of the tread compound itself is a very important factor. A real need has been felt in the industry for a laboratory flexing machine which would rapidly and inexpensively give results comparable to those obtained in road tests in order to study the effect that variations in compounding have upon this type of failure. The authors have developed a simple machine which it was felt might be of interest in this connection. Illustrations 1 and 2 are front and side-view photographs of this machine. It consists of a rotor disk one inch thick keyed to the shaft of a 1/4 h.p. induction motor and radially slotted about its periphery to take twelve samples. Around this is a steel ring placed off center in relation to the rotor. The test samples are mold-cured slabs of rubber 1 inch wide, 1 1/8 inches long, and 3/16-inch thick, having two semi-circular grooves molded across their width. When placed in a slot of the rotor, a test piece is held in place by a tightly-fitting cylindrical steel pin which fits in one of the semi-circular grooves in the test piece and in a similar groove cut in the wall of the slot.
Some Practical Methods of Measuring Gauge at the Calenders
Authors: Dieterich E. O. 
Published: February 2011

Abstract
A LITTLE reflection will immediately establish the fact that it is necessary to control, in some manner, the thickness of practically every stock delivered by a calender, and that this control is indicated by the twin considerations of quality and cost. As an illustration, consider coated fabrics used for tire carcass construction. From the standpoint of quality the skim coat applied to the fabric during calendering must be of sufficient thickness to insure adequate insulation between the plies in the completed tire. Not only must the average thickness be more than a certain minimum but it must be uniform, for non-uniformity results in heavy gauge in some regions and light gauge in others, the latter being a fruitful source of failure by ply separation in service, on account of excessive stresses developed by loading and traction. On the other hand, a skim coat which is too heavy may actually lead to deterioration in quality by introducing defects caused by increased difficulty in tire building. Another example that may be cited is the tread slab, tubed or calendered. Light gauge here may result in incomplete filling of the mold, producing blemished tires ; on the other hand, a tread slab that is too heavy may cause a more serious defect, buckled carcass, due to excessive rind at the mold register. In the case of solid tires, correct gauges are of utmost importance.