bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of Total Moisture in Carbon Blacks
Authors: Carson G. M. 
Published: February 2011

Abstract
IN THE course of an extended research on various grades of carbon black, determinations of total moisture were made by an adaptation of an old method. The method used was similar to one described by Allen and Jacobs (1) for measuring water in tar. The chief difference in the present method is that small amounts of moisture in carbon blacks must be weighed, whereas the larger amounts in tar could be measured. The difficulties in weighing the evolved moisture are described in the ensuing method of determination. Five grams of carbon black were placed in a 500-cc. round-bottom flask with 25 to 35 cc. of dry xylene and 200 cc. of dry mineral oil. A short air condenser led to the bottom of a 25-cc. distilling flask, which in turn was connected to two or more calcium chloride tubes. The flask containing the sample was heated to 150-175° C. in an oil bath, a stream of dry nitrogen being passed through the apparatus. The water and xylene were distilled into the small distilling flask and thence, by warming in a water bath, into the calcium chloride tubes, the current of nitrogen being continued. It required but a few minutes to remove the water from the xylene, indicated by the disappearance of cloudiness, and the calcium chloride tubes were then connected directly to the nitrogen line and the gas was passed through until the tubes reached constant weight. ylene is not adsorbed by calcium chloride and nitrogen does not remove water from it at room temperature during the time required for the experiment. The increase in weight of the calcium chloride tubes is the amount of water in the sample of carbon black. The amount of water thus determined is considerably higher than the 105° C. oven loss in 5 hours, and indicates that most of the moisture is of the “bound” or “capillary” type.
The Swelling of Latex
Authors: Evers F. 
Published: February 2011

Abstract
The swelling phenomena of latex in organic liquids such as benzene, toluene, or xylene were studied. As factors in the swelling power the following were observed: (1) the ammonia content of the latex; (2) the formation of a boundary layer in the surface of contact of both liquids. Ammonia-rich latex on contact with aromatic hydrocarbons forms a boundary layer which in turn swells, with a great increase in volume. Latex poor in ammonia forms no boundary layer and therefore does not swell. On the other hand, the hydrocarbon may diffuse into the latex without disturbing the Brownian movement. Subsequently the diffused hydrocarbon is able to bring about the swelling of the individual latex particles.
Studies of the Aging of Vulcanized Rubber. X.—The Relation between Degrees of Oxidation of Vulcanized Rubber and the Occurrence of the Maximum State of Acetone Extracts
Authors: Yamazaki Takeji , Okuyama Karoku 
Published: February 2011

Abstract
(1) Using the rubber-sulfur mixture and the mixture containing accelerator and zinc oxide, the relation between the maximum state of acetone extracts and the degree of oxidation was studied quantitatively. (2) In carrying out the above experiment, the samples previously extracted were used in order to accelerate the oxidation and to eliminate the influence of the free sulfur and rubber resin, etc. The aging was conducted at 70° C. for the rubber-sulfur stock and 70° C. and 90° C. for the stock containing accelerator and mineral filler and the increase of weight and the amount of the acetone extract were measured at definite intervals. The maximum state occurred in both cases, but for the case containing accelerator and filler the occurrence was comparatively slow. The decrease of acetone extract after the maximum state was shown to be due to partial formation of some acetone-insoluble products in the aged vulcanized rubber when oxidation proceeds considerably. (3) From the elementary analysis made on the aged samples from which acetone-soluble oxidation products were previously removed, it was shown that the oxygen content in these samples increased as aging proceeded.
The Solvation of High Molecular Substances, Especially Rubber
Authors: Stamberger P. , Blow C. M. 
Published: February 2011

Abstract
1. On the basis of new experimental data on rubber, the theories of the solvation of high molecular substances are discussed. 2. In this discussion the measurements of the swelling pressure of rubber in toluene are described. The values obtained, and also the measurements of the depression of the vapor pressure lead to the conclusion that rubber cannot be considered a mixture of homologous polymers. 3. The consistency or viscosity of gels is without effect on the decrease in the activity of the solvent (measured by the depression of the vapor pressure and the swelling pressure). 4. The conclusion is drawn that mastication cannot be considered a depolymerization. 5. On the basis of measurements of the viscosity of solutions of rubber-gas black compounds it follows that conclusions as to the molecular weight of the dissolved phase cannot be drawn from viscosity measurements without further ado. 6. The theories of the distribution of high molecular substances in solution are briefly discussed.
Isoprene and Rubber. XVII. The Fractionation of Balata
Authors: Staudinger H. , Bondy H. F. 
Published: February 2011

Abstract
On the basis of earlier experiments with synthetic materials, compounds of high molecular weight are not composed of a single substance, but consist of a mixture of homologous polymers. The individual members of a polymeric homologous series differ very little in physical and chemical properties, and therefore a mixture of polymeric homologous products such as is obtained in the polymerization of the monomer cannot as a rule be decomposed into simple compounds by means of solvents, but merely into mixtures of products of low and high molecular weight. Such separations have been carried out, for example, in the case of polyvinylace-tates, polystyrols, polyindenes, polyanetholes, and polyethyleneoxides. On the basis of these experiments it was assumed that natural products of high molecular weight likewise consist of a mixture of polymeric homologs. Thus purified rubber, for example, according to our views is not such a completely homogeneous hydrocarbon that all the molecules have the same length, but consists of a mixture of perhaps 100 or more polymeric homologs. Pummerer's decomposition of rubber into sol,- and gel-rubber, according to our experiments, is due to the fact that rubber consists of easily soluble polyprenes and difficultly soluble polyprenes, all belonging to the same polymeric homologous series. Of course there is the possibility that, in forming compounds of high molecular weight, nature produced primary molecules of uniform size, and that the mixture of polymeric homologs was formed only later through decomposition. In that case the natural products would differ in constitution from the synthetic material. They would not be polymerically uniform but completely uniform compounds in the sense of classical organic chemistry. The fact that in life processes methods are possible which we cannot realize in the laboratory is well known. Such a finding would not, of course, contradict our former view that natural products, such as rubber and balata, are of high molecular weight in the sense of classical structural chemistry. Our former work has indicated a similar structure for rubber and gutta-percha. Here it is simply a question whether or not the macromolecules of these natural products have a uniform length. In order to reach a decision, we first of all investigated balata, since it is prepared pure more easily than rubber. It was made from balata latex which was supplied to us through the courtesy of the management of the Norddeutsche Seekabelwerke, Nordenham." The balata thus obtained is a flocculent, cellulose-like mass, which looks like gutta-percha and crystallizes like it.
Isoprene and Rubber. XVIII. Viscosity Studies on Balata
Authors: Staudinger H. , Leupold E. O. 
Published: February 2011

Abstract
Varied views prevail as to the structure of the colloidal particles present in a rubber solution. According to Harries, Pummerer, and many others, these colloidal particles are formed through the association or aggregation of smaller molecules. According to Meyer and Mark they have a micellar structure, the micelles forming through the apposition of main valence chains. On the other hand, it was assumed by one of the present authors that the elementary particles in a colloidal solution of rubber are identical with the rubber molecules, these large, especially labile molecules being called macromolecules. Thus the existence of much larger molecules than any hitherto known was postulated. This view was confirmed by the conversion of rubber to hydro-rubber capable of forming colloidal solutions, and also by the pyrogenic decomposition of rubber. In order to decide definitely between the two conceptions, the stability of the colloidal particle in a rubber solution was studied by means of viscosity measurements at various temperatures as was done in the case of the polystyrols. If these colloidal particles form aggregates or if they have a micellar structure, they should decrease in size with increase in temperature, and this change should be evidenced by a diminution of the specific viscosity of the colloidal solution. On the other hand, if such a solution is composed of molecules, the specific viscosity at various temperatures is the same, provided that the molecules are not decomposed at higher temperatures. This line of research led to an explanation of the constitution of the colloidal particles in a polystyrol solution and was now applied to balata, since the latter is especially easily purified.
The Strength and Stretch of Double Texture Rubber Goods
Authors: Knowland T. M. 
Published: February 2011

Abstract
RUBBER articles may be divided roughly into three classes: (1) pure gum, (2) hard rubber, and (3) various combinations of rubber and textile fibers. This latter class is the largest and possibly the most important of the group, and includes besides tires the bulk of mechanical goods, such as hose, belting and sheet goods of various kinds. Probably no combination of useful materials affords a wider range of possibilities than the various combinations of rubber and textile fibers. In rubber-textile combinations the cotton fiber is ordinarily used to impart tensile strength and to decrease the stretchiness of the product, while the attempt is made to retain at the same time as much resiliency as possible. Most of these combinations are of laminated construction, consisting of alternate layers of rubber compound and woven fabric, the physical properties being controlled by the construction of the fabric and the composition and cure of the rubber compound. Since cotton is usually more expensive on a volume basis than rubber, it is desirable to obtain the maximum tensile properties of the cotton fiber and to restrict its use as much as possible. That this is a difficult matter may be recalled when we compare the actual bursting strength of various mechanical goods with the so-called theoretical or calculated strength based on the additive strengths of the plied up fabrics in the fabricated article; it is at once apparent that only a small proportion of the fiber strength is effectively employed.
Laboratory Flexing Tests as an Aid in Investigating the Pneumatic Tire Carcass
Authors: Depew H. A. , Jones H. C. 
Published: February 2011

Abstract
TIRE tests, both service and test wheel methods, are generally used for carcass development, supplemented to a limited extent by laboratory tests, which include stress-strain tests on the compound and the cord, friction tests to measure the force necessary to pull the rubber compound from the cord, and pulley flexing tests. Owing to the cost and difficulty of reproduction of tire tests, it is desirable to use laboratory tests in so far as possible, although it will be impractical to eliminate tire tests as final checks before putting laboratory information into production and as a general method of attack for special problems in design. Among the important problems that lend themselves especially well to laboratory methods are: (1) Insulation of tire cord, including thickness of skim and spacing of the cord; and (2) rubber compounds (both before and after aging), including composition and state of cure. In choosing laboratory methods, it was decided to use flexing methods, with tension tests on the compound as an aid in judging state of cure. Friction tests were not made since they would be meaningless for indicating the bond between rubber and cotton when the cords are well separated in rubber.
3-Methyl-1,3-Pentadiene
Authors: Fisher Harry L. , Chittenden F. D. 
Published: February 2011

Abstract
3-Methyl-1,3-pentadiene can be prepared pure without difficulty. However, unlike butadiene, isoprene, piperylene, and 2,3-dimethyl-1,3-butadiene, it apparently does not polymerize to an elastic, resilient solid product, and therefore the polymerization of 1,3-dienes to rubber-like products does not depend solely on the presence of the vinyl group.
Studies in the Vulcanization of Rubber. III—Kinetics of Vulcanization of Rubber with Sulfur and Selenium
Authors: Blake John T. 
Published: February 2011

Abstract
A procedure for the determination of combined selenium in rubber has been evolved. The rate of combination of selenium and rubber has been ascertained under certain conditions and shown to follow a first-order equation. A minimum value for the molecular weight of rubber has been estimated. The formation of hard rubber under chosen experimental conditions has been put on a mathematical basis and has been shown to follow a second-order reaction. The soft- and hard-rubber reactions have been shown qualitatively to be successive reactions and the function of accelerators has been discussed. The theory explains the anomalous results obtained by previous investigators.
Effect of Pigmentation on the Work of Retraction of Rubber Compounds
Authors: Conover F. S. 
Published: February 2011

Abstract
THE reënforcement of rubber by pigments has been studied by a number of investigators (4, 5) by considering the effect of pigmentation on the extension stress-strain curves and on the areas enclosed between these curves and the elongation axes, which areas are a measure of the work of extension. (Figure 1) These investigations, in conjunction with other data, have developed two opinions concerning the mechanism of reënforcement; one (2), that reënforcement is caused by a bond between the rubber and the pigment particles; the other (3), that reënforcement is primarily a function of the particle size of the pigment and that the bond is of secondary importance. The work cited above shows that pigments exert different effects on work of extension, and it has consequently been assumed that they would have somewhat similar effects on work of retraction as measured by the areas enclosed between the retraction curves and the elongation axes. (Figure 1)
Various Ozonides of Rubber and the General Question of the Existence of Primary Ozonides
Authors: Pummerer R. 
Published: February 2011

Abstract
Harries was the first to make use of ozone cleavage at the carbon double bond of unsaturated compounds as an important method of research in organic chemistry. However, the formula (see PDF for diagram) of Harries, which is founded on its analogy with the products of other addition reactions, rests on scanty experimental data. One of the chief arguments against the formula is the absence of glycols as reaction products by the action of the most varied types of reducing agents. This latter fact, in conjunction with certain polymerization phenomena, led Staudinger to propose an isoozonide type of formula, in which the carbon chain has been opened, thus (see PDF for diagram) According to Staudinger, these isoozonides are formed very readily by transposition from primary or molozonides, and they are stable compounds. On the contrary, some molozonides are stabilized by polymerization. The constitution of butylene ozonide was proved synthetically by Rieche and Meister to be that of an isoozonide, and today the isoozonide formula has received general acceptance. In spite of these facts, some of the results of Harries, on which he based his original ozonide formula, remain unchallenged; for instance, the fact that when heated the ozonide of mesityl oxide reverts to mesityl oxide, and the fact that fumaric acid forms with ozone a loose compound from which ozone is liberated easily. In view of this, it appeared as if the Harries formula would really turn out to be the correct one, and that stable molozonides should exist.
Fatigue in Rubber. Part I
Authors: Cassie A. B. D. , Jones Maldwyn , Naunton W. J. S. 
Published: February 2011

Abstract
1. An apparatus is described for the measurement of the dynamic Young's modulus and associated frictional forces. 2. A modified apparatus is described for the measurement of the rigidity modulus and associated frictional forces. 3. The frictional loss of a rubber mixed with acetylene black is midway between the losses of rubbers mixed with gas and lamp black, respectively. 4. The frictional loss of rubber mixed with any form of carbon black falls with increase in temperature. 5. The moduli of rubbers containing gas and acetylene black decrease with increasing temperature, whereas those containing lamp black increase with increasing temperature similar to that of an unloaded rubber. 6. Frictional losses increase with cure, but the change becomes small around the optimum cure. 7. Antioxidants have a definite effect upon frictional loss quite apart from any effect due to alteration of degree of cure.
A Preliminary Study of the After-Effect or Drift in Rubber under Constant Load
Authors: Braun Milton L. 
Published: February 2011

Abstract
When a suitable weight is supported by suspension from a piece of rubber, as a stationer's band, the rubber may be stretched any amount up to several times its original length, but its new length is not constant; it increases with time. The increase in length with time is variously known as “after-effect, #x201D; “creep,” “drift,” “flow,” or “time-yield.” This phenomenon, which seems to have been very incompletely investigated, was probably first recognized by Dietzel in 1857. Kohlrausch in 1875 made an entensive study of both torsional and linear after-effect in metal, glass, and rubber. The load used by Kohlrausch on rubber were, however, exceedingly small, and the duration of drift was limited to one day. He came to the conclusion that drift in rubber followed a power law for the first sixty minutes. During the next decade Pulfrich slightly extended the work of Kohlrausch by experimentation on a red rubber tube, using elongations up to 150 per cent, with maximum observation time of 15 days. He concluded that the power law of Kohlrausch held for at least thirty minutes of drift. In 1903, Bouaase and Carrière observed the after-effect (in pure gum and sulfur cords of 4 mm. diameter and of specific gravity 0.984) under a great variety of experiments, and concluded that drift was to be expressed by an exponential or logarithmic law rather than by a power function. Both Phillips and Schwartz arrived at similar conclusions. More recently Ariano reported that the drift proceeded at a decreasing rate which finally assumed a constant value either finite or zero. Van Geel and Eymers found that for milled rubber the drift continued until the specimens broke, but that for rubber obtained by evaporation of latex all after-effect ceased within three minutes. Shacklock noted that creep took place for some hours and then reached a limit. Evidently more light needs to be cast on the probem of the drift effect in rubber. Two preliminary experiments on drift are herein considered; Part I on general trends, and Part II on more specific analysis of the effect as observed in one specimen.
Chemistry of Soft Rubber Vulcanization. V. Treatment of Dilute Rubber Cements with Sulfur Chloride
Authors: Garvey B. S. 
Published: February 2011

Abstract
PREVIOUS investigations (5, 6, 7, 8) indicated that vulcanization of rubber involves the establishment of a mechanical structure in the mass. This structure is apparently produced by changes in the hydrocarbon brought about by two chemical reactions: (a) addition of the vulcanizing agent and (b) a reaction of the hydrocarbon catalyzed by the vulcanizing agent. The experiments reported in this paper are concerned with the effect of sulfur chloride on the viscosity of dilute rubber cements under various conditions and with the solubilities of films obtained by evaporating cements treated with sulfur chloride. Consideration of the results has suggested a new interpretation of the nature of vulcanization. Experiments of a somewhat similar type have been reported by Bernstein (1, 2, 3), Fromandi (4), Kirchhof (10, 11), LeBlanc and Kröger (12, 13), Porritt (16), and Weber (18). In most of their investigations they used 100 per cent by weight of sulfur monochloride on the rubber. Since ordinary cold-cured articles contain about 1 per cent of sulfur monochloride, the effect of this small amount is most significant.
“Colloidal” Zinc Oxide
Authors: Curran H. A. , Dawson T. R. 
Published: February 2011

Abstract
Some ten years ago, when so-called “colloidal” zinc oxides were being introduced to the rubber manufacturing industry, two samples were investigated to determine their behavior in rubber compared with ordinary good quality zinc oxide used in rubber. According to accounts published at the time, “colloidal” zinc oxide possesses an average particle size just within the limit of resolution of high-power microscopes, and an average particle diameter of 0.15 micron. In rubber it has been claimed to impart superior reinforcement, higher tensile strength, greater resistance to abrasion, and enhanced activation of organic accelerators. In the following report, samples A and B represent two samples of the same grade of “colloidal” zinc oxide, and C a good grade of regular zinc oxide.
The Constitution of Inorganic Rubber
Authors: de Ficquelmont Armand Marie 
Published: February 2011

Abstract
There is a complete series of phosphonitrile chlorides of the general formula, (PNCl2)x, of which (PNCl2)3, (PNCl2)4, (PNCl2)5, (PNCl2)6, and (PNCl2)7 are already known. All these compounds have the remarkable property of changing rapidly around 350° C. into an amorphous substance which is insoluble and infusible, and whose mechanical properties are similar to those of rubber. It is, for this reason, generally known as inorganic rubber. According to the various authors who have studied this substance, the latter is a mixture composed solely of phosphonitrile chlorides of very high molecular weights. In the present paper, it will be shown that, contrary to this hypothesis, inorganic rubber, like all the gums obtained by Renaud at low temperatures, must contain, besides highly polymerized compounds which form a sort of network, lower members of the series which are confined in the meshes of this network. This assumption makes possible a simple interpretation of all the apparent phenomena of depolymerization of inorganic rubber which have been described up to the present time.