bluuebunny/crossref_metadata_2025_split huggingface dataset:
New Derivatives of Rubber
Authors: Bruni Giuseppe , Gieger E. 
Published: February 2011

Abstract
ALTHOUGH the numerous researches of Harries, Staudinger, Pummerer and their collaborators have in recent years enriched our knowledge of the chemistry of rubber, the number of derivatives of rubber prepared up to the present is very few, and the number of atomic groups or radicals which it has been possible to introduce in the polyisoprene chain is still smaller. The reason for this is that rubber itself and its halides and hydrohalides have only a limited reactivity because of their colloidal nature and their slight solubility. Among those already known, the most interesting derivative is that obtained many years ago by C. O. Weber by the action of phenol on rubber dibromide. This was considered by Weber to be a phenolic ether, whereas Fisher, Gray and McColm have recently shown that it is a condensation product of hydrorubber and has free phenol groups.
Importance of Temperature and Humidity Control in Rubber Testing. Progress Report of the Physical Testing Commitee, Rubber Division, A.C.S. (Dated Dec. 8, 1927)
Authors: Partenheimer J. E. , Bridgwater E. R. , Cranor D. F. , Curtis E. B. , Schade J. W. , Shepard N. A. , Somerville A. A. , Vogt W. W. , Wormeley P. L. 
Published: February 2011

Abstract
The purpose of the work which this committee has undertaken is to determine the effect of the variables which influence the results of physical tests on rubber. The investigation has proven that variations in temperature which may occur from day to day in an uncontrolled testing room may affect the physical tests to as great a degree as a 25 to 40 per cent change in the time of cure, while relative humidity affects the results to only a minor degree. Furthermore, variations in the absolute humidity of the room in which the unvulcanized rubber is stored between the time of mixing and the time of curing may affect the tensile strength and modulus of rubber compounds to as great a degree as does the temperature after curing. It is, therefore, apparent that laboratory tests which are conducted under uncontrolled conditions of temperature and humidity may give highly erroneous results and may even give misinformation which is worse than no information at all. The committee, therefore, recommends that mixed stock prior to curing and cured stock prior to testing be conditioned for not less than twenty-four nor more than twenty-eight hours at 82 deg. F. ± 2 deg. and 45 per cent relative humidity ± 3 per cent and that the testing room be maintained at 82 deg. F. ± 2 deg. If a temperature of 82 deg. F. cannot be maintained for conditioning the mixed stock prior to curing, the committee recommends a relative humidity corresponding to the temperature used which gives an absolute humidity equal to that obtained under the former conditions. The temperature of the testing room should be controlled within the above stated limits, but it is not necessary to control the humidity of the entire room. A small conditioning cabinet in which the standard humidity is maintained has been found to be sufficient.
Conversion of Rubber into Thermoplastic Products with Properties Similar to Gutta-Percha, Balata, and Shellac. I—Methods of Preparation and General Properties
Authors: Fisher Harry L. 
Published: February 2011

Abstract
By heating in sheet form a mixture of rubber with approximately 10 per cent of its weight of either an organic sulfonyl chloride or an organic sulfonic acid, for several hours at 125–35° C., the rubber is converted into tough, thermoplastic products resembling gutta-percha and hard balata. If heated similarly in bulk there is a pronounced exothermic reaction and the products formed are hard and thermoplastic like shellac. p-Toluenesulfonyl chloride and p-toluenesulfonic acid are suitable reagents. A mixture of 7.5 parts of p-phenolsulfonic acid and 100 parts of rubber, under similar conditions, gives a flexible product similar to gutta-percha, which is soluble in benzene, is a very good adhesive, and is the basis of the Vulcalock process.
Factors in Processing Reclaimed Rubber
Authors: Shoaff P. S. 
Published: February 2011

Abstract
Production of reclaimed rubber of uniformly good physical and chemical properties is dependent first upon judicious classification and blending of raw materials. Grinding to a state in which no large particles are present, but without an excess of fines, allows a minimum devulcanizing time at a given temperature, decreases the tendency to depolymerize to an objectionable extent, and reduces the requirement for softeners. These conditions facilitate further processing to a smooth product of good quality with the desired plasticity and with optimum compounding, milling, calendering, and tubing characteristics. Devulcanization at high temperatures tends to reduce the tensile slightly and to increase the elongation as compared with treatment at lower temperatures. Alkali reclaims require efficient washing to remove residual caustic and the recovery of fines from the wash liquors involves problems of settling and filtration or screening. Drying of wet-processed reclaims at high temperatures or for an excessively long time results in tacky products, just as does over-devulcanization. A minimum amount of milling and refining at normal temperatures is desirable to preserve the quality, therefore previous processing should be thorough and uniform. Some comparisons of types of equipment are made and some desirable future developments are discussed.
Protective Paint from Rubber
Authors: Gray Harold 
Published: February 2011

Abstract
A protective paint has been prepared from rubber which can be used commercially. The chief features of the new paint are: (1) good adhesion to metals; (2) resistance to acids, alkalies, corrosive gases, and corrosive chemicals in general; (3) low permeability to moisture, salt solutions, salt spray, etc.; (4) the film is tough and can be bent without injury at sub-zero temperatures; (5) the film does not flake when cut, and rust spreads very slowly from an exposed area. On account of its unusual set of properties, this paint should have a wide range of usefulness, particularly in chemical and other plants where metal parts are subjected to excessive corrosive conditions.
Effect of Heat on Raw Rubber
Authors: Park C. R. , Carson C. M. , Sebrell L. B. 
Published: February 2011

Abstract
A study has been made of the effect of heat upon crude rubber. Heating in steam for 24 hours at 158° C. plastifies the rubber to about the same extent as about five passes through a tight mill. The chemical characteristics are changed in such a way as to indicate that a portion of the protein materials and fatty acid esters has been hydrolyzed. The rate of cure is increased in the case of most crudes for mercaptobenzothiazole and pure-gum mixes, but is less affected in the case of hexamethylenetetramine, diphenylguanidine, and ethylidene aniline. The stress-strain curve is affected by the heating in such a way as to make it more convex toward the strain axis. A study has been made of the chemical constituents of the heated rubber which have been responsible for changes in curing characteristics. It is believed that the amines, nitrogen bases, and alkaloids are the principal active material responsible for the peculiarities of heated rubber.
Preparation of Butadiene
Authors: Birch Stanley Francis 
Published: February 2011

Abstract
OF THE numerous methods available for the preparation of butadiene in the laboratory, those described by Thiele and by Ostromuislenskii are probably the most convenient. Both, however, suffer from the disadvantages which usually characterize operations at comparatively high temperatures; the exact conditions are difficult to find, the process is long and tedious, and finally involves the separation of the required material from a complex mixture. It has long been known that butadiene occurs in the various products obtained when oils are heated to a high temperature. Caventou first isolated butadiene in the form of its tetrabromide from illuminating gas, and Armstrong and Miller definitely established the presence of butadiene in the liquid obtained by compressing oil gas. The work of numerous later investigators has confirmed their results and has shown that the more drastic the heat treatment to which the oil is submitted the greater is the tendency for butadiene to be formed. For this reason vapor-phase cracking of petroleum, which is carried out at a much higher temperature than liquid-phase cracking, yields products specially rich in butadiene.
“Normal Aging” of Compounded Rubber
Authors: McKee Ralph H. , Depew Harlan A. 
Published: February 2011

Abstract
Nine compounds were chosen for an investigation of “normal aging” under various conditions and after different times of storage. The report is divided into three parts: (I) aging of cured test slabs stored under different atmospheric conditions, including wet and dry; (II) aging of rubber under strain; (III) comparative aging of cured and uncured rubber. Tables and curve sheets selected from a large mass of data are given to illustrate how these nine rubber compounds age. THE aging of rubber products is the net resultant of chemical reactions and changes of a physico-chemical nature. It has long been recognized that conditions of storage have an important influence on the normal aging of rubber products. Rubber products stored in a warm place deteriorate more rapidly than when stored in a cold place, and it probably was recognition of this fact that led to the development of the Geer accelerated-aging test, which accelerates aging solely by increasing the temperature during storage. Oxygen is also an important factor in the aging of rubber products. In normal storage the oxygen concentration varies very little, and depends only on the barometric pressure.
Carbon Blacks and Their Use in Rubber. II—Experiments in Cured Rubber
Authors: Goodwin Norris , Park C. R. 
Published: February 2011

Abstract
This is the second part of a study of several carbon blacks to determine what characteristics of the black are most largely responsible for imparting to rubber those properties which will make for long life in a tire tread. In Part I the characteristics of the blacks themselves as well as their behavior in uncured rubber were compared. This article discusses their action when compounded in cured rubber stocks containing various accelerators—mercaptobenzothiazole, diphenylguanidine, hexamethylenetetramine, ethylidene-aniline, litharge—and a base mix of rubber and sulfur. IN ORDER to determine what factors in the physical make-up of a given carbon are most largely responsible for the behavior in rubber which determines its suitability in a tire tread, it is essential that we should know what particular property or properties of rubber are responsible for long life in a tire tread and what measurable characteristics of rubber may be used as an index of the life of the tire tread. It has been variously held that tensile, stiffness, resilient energy, etc., are measures of resistance to abrasion. With such a wide diversity of opinion it would be obviously unwise to lay too much weight on any one property.
Plasticity Determinations in Crude Rubber. Influence of Different Factors on the Changes in Plasticity When Keeping the Rubber
Authors: de Vries O. 
Published: February 2011

Abstract
Rubber that contains less than the normal proportion of serum substances shows a larger increase in plasticity on keeping than the ordinary plantation product. Coagulation from latex diluted 1: 1 has a distinct effect, coagulation from latex diluted 1: 9 has a marked effect in this direction; extraction by soaking in water, or washing during milling, may have an appreciable effect. As rubber that contains all the serum substances gets harder on keeping, there must be—presumably at a content of serum substances in the region of that of normal plantation rubber—a point where the plasticity remains about constant on keeping. This proportion of serum substances may be regarded as the most desirable from the standpoint of uniformity, especially constancy in plasticity on keeping. The changes in plasticity on keeping are little influenced by the age of the trees (soft rubber from young trees changes little on keeping), by the nature of the acid (acetic or formic) and the proportion of acid used for coagulation, by mechanical treatment (rolling to sheet or crepe, milling a smaller or larger number of times), by heating during drying and by smoking. The rubber gets very weak on keeping when a large dose of sodium acetate bad been added to the latex; finely cut (not washed) pieces from matured coagulum get very weak on keeping, in contrast to crepe from matured coagulum that gets somewhat harder on keeping, about as or somewhat more so than ordinary crepe. Coagulation by heating has little influence; coagulation by alcohol seems to cause the rubber to get somewhat softer on keeping. Crepe from ammoniated latex changes about in the same way as the control from fresh latex; films from ammoniated latex evaporated in the air got very hard on keeping, just as films from fresh evaporated latex.
The Reactions of Aniline and Its Homologs as Accelerators of Vulcanization
Authors: Kimishima Takeo 
Published: February 2011

Abstract
The accelerating action of aniline and its homologs can be considered from two points of view. The one is whether there are exothermic phenomena caused by the accelerators and the effect of those phenomena upon vulcanization. The other is the chemical effect upon vulcanization caused by reaction products derived as a result of chemical reaction of an accelerator and sulfur. In other words, the object of consideration in the former is the effect of thermal change, while that in the latter is the effect caused by chemical change. Leaving the former for later discussion, the writer will first describe the result of his experiments concerning the reaction products of accelerators and sulfur and the effect of these products upon vulcanization. In an investigation of this kind it is extremely difficult to extract and determine the effective elements from material derived from an accelerator in the process of vulcanizing reactions of rubber. No case has yet been known where a satisfactory result was realized by such a method. Therefore, the writer has first taken up the investigations of reactions of an accelerator with sulfur and by separating and refining each of the various reaction products approached the matter of vulcanization itself, and under various conditions caused these reaction products to act upon rubber. Thus the writer has followed the plan of establishing the reaction mechanism of accelerators by seeing the changes, both chemical and physical, together with their effect upon vulcanization.
A New Tetramethylbutadiene
Authors: Macallum A. D. , Whitby G. S. 
Published: February 2011

Abstract
The present investigation was undertaken largely as part of a study of the influence of methyl substitution on the polymerizability of butadiene. The data available on the way in which and the extent to which polymerization is affected by the position and the number of methyl groups which may be introduced as substituents into the molecule of butadiene are far from complete. Both the a- and the b-methylbutadienes are polymerizable to rubbers. Of the dimethylbutadienes, the bg- and ad- are polymerizable; the gem-dimethyl compound appears, according to observations of Kyriakides and others, to be polymerizable, but according to a statement of Harries only with difficulty. It would appear that methyl substitution in the terminal positions of butadiene has, compared with such substitution in the middle positions, an unfavorable effect on the ease of polymerization. It would appear, further, from the limited data available, that increase in the number of methyl substituents in butadiene diminishes the ease of polymerization, since bg-dimethylbutadiene polymerizes less easily than isoprene and ad-dimethylbutadiene less easily than piperylene. The available information regarding the polymerizability of tri- and tetramethylbutadienes is very meagre. The known trimethylbutadienes (aag- and aad-) have not been studied from the point of view of polymerization. From its behavior on distillation, Pribytek considered aadd-tetramethylbutadiene (diisocrotyl) to show an inclination to polymerize, and it has been mentioned in the patent literature as polymerizable. Lebedeff, however, found it to be practically lacking in ability to polymerize when heated at temperatures up to 250. Another tetramethylbutadiene which has been described, viz., the aagd-compound, has not been studied in regard to polymerization.
Recent Scientific Advances in Connection with Guayule
Authors: Spence David 
Published: February 2011

Abstract
RECENT scientific advances in connection with guayule have been made along botanical and biological as well as chemical lines. The work of Dr. W. B. McCallum in definitely identifying many different varieties of guayule and subsequently propagating in California a few selected strains that best respond to intensive cultivation marks a distinct advance in the scientific development of this subject, and his successful efforts in seed selection and propagation will always stand as a monument to his skill and perseverance in this connection. His work is not only of fundamental importance in any study of the effect of environment on natural growth, but also has clearly shown that the available rubber or yield of rubber from the shrub is determined to a large extent by the variety of shrub which is cultivated. The bridge between mariola, with its three per cent of available rubber, and the best varieties of guayule as now growing in California, is apparently spanned by an almost infinite number of varieties of guayule differing in form, size, color, rate of growth, etc., as well as in their hydrocarbon content.
Sources and Application of Cooling Water
Authors: Jennings H. K. 
Published: February 2011

Abstract
IN the Firestone plants, the application of water for cooling purpose has progressed from year to year along the following lines. The original installation of mill rolls included a stuffing box in one end of the roll, with two 1 1/2″ holes in the end of this stationary box, one being the water inlet with a 1″ perforated standard pipe extending across the entire length of the inside of the roll. The coding water filled the entire cavity of the roll, placing it under line pressure with a drain through a 1″ pipe to the other connection in the stationary stuffing. box. This water is returned to a common header system and finds its way into the storm sewer system. This method of mill roll cooling required approximately 40 gallons of water per mill per minute, the water entering the roll at a temperature of 56° and leaving at approximately 60°, or a temperature rise of only 4° F. With this method, the difference between the temperature of the outgoing water and the stock was 85°. This method was exceedingly inefficient and used a large quantity of this scarce well water. Several years later it became necessary that more efficient means be found for cooling mill rolls. At that time the engineers designed an aluminum fin vane that extended the entire length of the inside roll cavity with a tip that forced the water directly against the inside surface of the steel roll. This aluminum vane also acted as a paddle which kept the water agitated as the roll revolved, and coming more rapidly in contact with the roll surfaces.
Chilled Iron Rolls in the Rubber Industry
Authors: Pickering N. W. 
Published: February 2011

Abstract
PROBABLY no single part of a machine is more vital to the manufacture of rubber products than the chilled iron roll. It is used in most operations from the cracking and washing of the crude rubber to the final accurate calendering where the variation is limited to fractional thousandths. As you gentlemen are familiar with the history and development of the rubber industry, it is not necessary to go into any details connected therewith, but it might be well to recall to your mind the fact that the vulcanizing of rubber was developed in the year 1844 at Naugatuck, Connecticut, a town located about ten miles from Ansonia, where Farrel Foundry and Machine Company was started in 1848. The discovery of the vulcanizing process made possible the practical use of rubber, and manufacturing of the product on a small basis very soon started, developing into one of the largest industries of the United States. In Mr. Farrel's diary of 1854 there is an entry regarding his negotiations with a Mr. Goodyear of Naugatuck, and finally the memorandum of agreement of sale of a three-roll 20×48″ calender for $2,400 and a four-roll 20 × 48″ calender for $3,400. The calenders were designed and built but the chilled iron rolls had to be imported from England. There were already some mills in this country which had imported chilled iron rolls for rolling copper and brass products and for calendering paper.
Open Mill Mixing vs. Internal Mixers
Authors: Crisp P. P. 
Published: February 2011

Abstract
AT the present time about 80 per cent of all the mixing at the Miller Rubber Company is done in internal mixers. All tires, tubes, heels and in fact all stocks with the exception of highly colored bath caps, water bottles and the like are mixed on these machines. The transition from mill to internal mixer has been gradual as there were many difficulties to iron out, both in the original mixer itself as well as in the operation. Our first experience with the internal mixer dates back to 1916 when we installed a small machine. The troubles encountered with this machine were largely due to the inability of getting rid of the heat generated during the mixing operation. In 1919 we installed the first mixer with which we mixed tire tread socks with some degree of success. Our biggest difficulty at this time was not the dispersing of the powders or pigments in order to meet gravity and tensile specifications, but was rather due to the fact that the mixed stock refused to run through the calendars and tube machines on account of being too stiff.
Dispersion of Pigments in Rubber. I—Microscopical Studies of Agglomeration and Flocculation
Authors: Grenquist Ernst A. 
Published: February 2011

Abstract
A literature review has been given dealing chiefly with the different factors that influence and regulate the dispersion of pigments in rubber, especially agglomeration and flocculation. Suggestions have been offered in regard to the validity of different physicochemical dispersion laws for the system rubber—pigment. The nature of agglomeration and flocculation of carbon black and zinc oxide has been described. Experimental evidence has been presented showing changes taking place in the dispersion of pigments during vulcanization. The distribution of carbon-black pigments in highly compounded treads has been discussed. The particles appear to assume a loose network formation which perhaps is an indication of the reënforcement of the system.
Carbon Black. I—A Study of Its Volatile Constituents
Authors: Johnson C. R. 
Published: February 2011

Abstract
The rates of evolution of gas from carbon black with variation of time, temperature, and pressure have been determined. Complete analyses have been made of five types of carbon black, which involve an organic combustion of the original sample, an organic combustion of the sample after the gases have been removed, a determination of the loss in weight represented by the gases removed, analyses of the gases removed, and finally a complete accounting, or balance, of the carbon in the steps considered. In an attempt to supply some missing information not revealed by the foregoing, some special gas analyses under varying conditions were made. The relationship between the amount and composition of volatile matter evolved from carbon blacks and the properties imparted to vulcanized rubber when compounded with these blacks has been studied.