S. K.—The Russian Synthetic Rubber from Alcohol. A Survey of the Chemistry and Technology of the Lebedev Process for Producing Sodium-Butadiene Polymers

1942 ◽  
Vol 15 (3) ◽  
pp. 403-429 ◽  
Author(s):  
Anselm Talalay ◽  
Leon Talalay
Keyword(s):  
Natural Rubber ◽  
Petroleum Products ◽  
Economic Independence ◽  
Russian Government ◽  
Experimental Station ◽  
Synthetic Product ◽  
Synthetic Rubber ◽  
Economic Council ◽  
Factory Layout ◽  
Continue Work

Abstract The question of producing synthetic rubber industrially was raised in Russia as early as 1918, and was fostered principally by the quest of the U.S.S.R. for economic independence. Having recognized that 1,3-butadiene is one of the simplest organic compounds capable of being polymerized to a rubberlike substance, the Russian Government provided funds for research in two directions: (1) To investigate the possibility of obtaining butadiene from a mixture of ethyl alcohol and acetaldehyde, according to the method suggested by Ostromislensky in 1915, for which purpose a pilot plant was erected in Moscow at the Bogatyr Rubber Company. (2) To continue work started in 1915 by B. V. Buizov in the laboratory of the Leningrad Treugolnik Rubber Plant, using petroleum products as a source of butadiene. By 1922 the Moscow plant had proved that Ostromislensky's process had no industrial future, for it yielded only 5 to 6 per cent of butadiene instead of the 15 to 18 per cent originally expected. The experimental station operated by Buizov had likewise met with little success by 1925. Early in 1926, therefore, the Superior Economic Council of the U.S.S.R. announced an open competition for the best industrial method of producing synthetic rubber, setting January 1, 1928 as the deadline. The qualifying conditions were rather exacting. They specified that the synthetic rubber should be neither inferior in quality to, nor substantially different in price from, natural rubber. Aside from a detailed description of the process and a two-kilogram sample of the synthetic product, the competition called for plans of a complete factory layout for its manufacture.

Vistanex Polybutene—Rubber Blends

1941 ◽  
Vol 14 (2) ◽  
pp. 386-397 ◽  
Author(s):  
S. Longman
Keyword(s):  
Natural Rubber ◽  
Raw Materials ◽  
Petroleum Products ◽  
The Other ◽  
Partial Substitution ◽  
Manufacturing Equipment ◽  
Rubber Industry ◽  
Rubber Blends ◽  
Synthetic Rubber

Abstract From the foregoing data on blends of Vistanex Polybutene and rubber, it is evident that these two materials complement one another. Each has properties which the other lacks, and blends of the two can be made to emphasize the more desirable properties of either one. Extreme flexibility in compounding these blends is possible, since they are perfectly compatible in milled compounds. Therefore, great latitude is given in compounding of these blends to secure any range or degree of properties possible with either of the components. Vistanex Polybutenes should not be considered as synthetic rubber, because they will not vulcanize, and they lack certain characteristics of vulcanized natural rubber. More properly Vistanex Polybutenes should be considered as modifying agents for partial substitution of natural rubber. In many cases, this substitution of a part of the natural rubber in a compound by Vistanex Polybutene confers definite advantages and improves qualities of such compounds for special uses. Therefore, Polybutenes, even in normal times, have a very definite field of usefulness and, in the event that imports of natural rubber become restricted, the availability of the Vistanex Polybutenes in quantity will be of increasing importance to the rubber industry. Since the raw materials for the manufacture of Vistanex Polybutene are petroleum products, the availability of raw materials is a source of no difficulty in this country. Likewise, the manufacturing equipment is not excessively expensive, and, with expanded production, lowered prices may confidently be expected.

Chlorinated Isoprene Rubbers in Adhesive Composites

2017 ◽  
Vol 44 (5) ◽  
pp. 25-28 ◽  
Author(s):  
A.A. Zuev ◽  
L.R. Lyusova ◽  
N.P. Boreiko
Keyword(s):  
Natural Rubber ◽  
Scientific Research ◽  
Scientific Research Institute ◽  
Physicomechanical Properties ◽  
Butadiene Rubber ◽  
Technological Factors ◽  
Nitrile Butadiene Rubber ◽  
Synthetic Rubber ◽  
Adhesive Materials ◽  
Isoprene Rubber

Now there is not a single area of industry that can do without adhesive elastomer materials. Composites based on synthetic rubbers comprise 75% of the total volume of adhesive materials produced, which is due to the combination of unique properties typical of the elastomer base of the adhesive. The base of many imported adhesives for the bonding of rubber to metal is chlorinated natural rubber. As an alternative, chlorinated synthetic isoprene rubber has been proposed, developed at the Scientific Research Institute for Synthetic Rubber in St Petersburg. The chlorinated isoprene rubber was compared with imported chlorinated natural rubber in adhesive composites, and the physicomechanical properties of mixes based on a blend of chlorinated rubber and nitrile butadiene rubber were investigated. The investigation was conducted on chlorinated natural rubber of grade Pergut S20, chlorinated isoprene rubber SKI-3, and nitrile butadiene rubbers of grades BNKS-28AMN and SKN-26S. The influence of the ratio of chlorinated rubber to nitrile butadiene rubber and the technological factors of mix preparation on the properties of films produced from them was established. It was shown that, in terms of the level of properties, home-produced chlorinated rubber can be used as the base for adhesives for hot bonding of rubber to metal instead of imported Pergut S20.

scholarly journals Sustainability and Competitiveness of Thailand’s Natural Rubber Industry in Times of Global Economic Flux

2017 ◽  
Vol 14 (1) ◽  
pp. 169
Author(s):  
Palapan Kampan
Keyword(s):  
Natural Rubber ◽  
Positive Relationship ◽  
New Technologies ◽  
Pearson Correlation ◽  
The United States ◽  
Bivariate Correlation ◽  
Synthetic Rubber ◽  
Reinforcing Factors ◽  
Strong Positive Relationship ◽  
Correlation Tests

This study assesses economic, legal, and environmental conditions that Thai rubber farmers face, and evaluates actions they can take to increase incomes. Statistical analyses determine relationships between prices of oil, natural and synthetic rubber. Pearson correlation tests found a strong positive relationship (r = 0.887) between the price of Brent crude and Thai ribbed smoked sheets, and a moderate positive relationship between price changes in Brent and synthetic rubber (r = 0.648). Regression analysis showed Brent oil price is a good predictor of natural rubber prices. Moderate to strong positive relationships were also found between natural rubber price and gross domestic product of Japan, China, and the United States. Criminal antitrust behavior in rubber industries appeared to interfere with normal pricing in rubber markets. No significant bivariate correlation was found between rainfall in Thailand and natural rubber price, production, or export although flooding and other environmental issues clearly affected rubber farms. A survey of options showed Thai rubber farmers can improve livelihoods best through collective purchase and use of new technologies, and by integrating into downstream supply chain industries. At very least, farmers are urged to abandon monocrop methods and supplement incomes with fruit, fish, livestock, or pigs. stment budget, 2) architectural Aesthetic, and 3) utilization. Additionally, background of the interviewees is one of reinforcing factors for decision on universal design investment.

Determination of Peroxides in Synthetic Rubbers

1945 ◽  
Vol 18 (4) ◽  
pp. 874-876
Author(s):  
Richard F. Robey ◽  
Herbert K. Wiese
Keyword(s):  
Molecular Weight ◽  
Natural Rubber ◽  
Quantitative Determination ◽  
High Molecular Weight ◽  
Active Oxygen ◽  
Lower Molecular Weight ◽  
Synthetic Rubber ◽  
High Molecular Weight Polymers ◽  
Methanol Solutions

Abstract Peroxides are found in synthetic rubbers either as the result of attack by oxygen, usually from the air, or as a residue from polymerization operations employing peroxide catalysts. Because of possible detrimental effects of active oxygen on the properties of the rubber, a method of quantitative determination is needed. The concentration of peroxides in substances of lower molecular weight may be determined with ferrous thiocyanate reagent, either titrimetrically as recommended by Yule and Wilson or colorimetrically as by Young, Vogt, and Nieuwland. Unfortunately, many highly polymeric substances are not soluble in the acetone and methanol solutions employed in these procedures. This is also the case with hydrocarbon monomers, such as butadiene, containing appreciable concentrations of soluble high molecular weight polymers. Bolland, Sundralingam, Sutton and Tristram recommended benzene as a solvent for natural rubber samples and the reagent made up in methanol. However, most synthetic rubbers are not readily soluble even in this combination. The following procedure employs the ferrous thiocyanate reagent in combination with a solvent capable of maintaining considerable concentrations of synthetic rubber in solution. The solvent comprises essentially 20 per cent ethanol in chloroform.

scholarly journals Fatigue behaviour of an industrial synthetic rubber

2018 ◽  
Vol 165 ◽  
pp. 22004 ◽  
Author(s):  
Thomas Balutch ◽  
Bertrand Huneau ◽  
Yann Marco ◽  
Pierre Charrier ◽  
Clément Champy
Keyword(s):  
Natural Rubber ◽  
Fatigue Cracks ◽  
Fatigue Behaviour ◽  
Fatigue Tests ◽  
Damage Scenario ◽  
Root Cause ◽  
Synthetic Rubber ◽  
Initiation And Propagation ◽  
Cause Of Failure ◽  
The One

For some automotive anti-vibration applications, for instance exhaust hangers, center bearing bushes or torsional vibration dampers, temperature constraints make the use of synthetic rubbers, such as EPDM, necessary because of their better heat aging resistance compared to natural rubber. The aim of this paper is to understand the features of the fatigue behaviour of an industrial EPDM compared to the wellknown natural rubber. To do so, fatigue tests are conducted on hourglass-shaped specimens, and fracture surfaces are analysed using optical microscopy and scanning electron microscopy (SEM). It appears that every samples exhibit only one root cause of failure. Thus, two types of precursors are identified as responsible of the final fracture of samples: material’s inclusions and mold flaws. Interrupted fatigue tests are then performed and fatigued samples are observed with SEM. The built procedure allows us to follow fatigue cracks initiation and propagation along cycles, and to propose local damage mechanisms for each type of precursors. A global damage scenario is finally considered and compared to the one of natural rubber described in the literature.

Ski Rubber, Polyisoprene, Similar to Natural Rubber

1958 ◽  
Vol 31 (1) ◽  
pp. 30-43
Author(s):  
K. F. Anikanova ◽  
G. E. Betts ◽  
V. G. Zhakova ◽  
N. F. Komskaya ◽  
B. K. Karmin ◽  
...  
Keyword(s):  
Natural Rubber ◽  
Scientific Research ◽  
Scientific Research Institute ◽  
Structural Element ◽  
Molecular Weights ◽  
Synthetic Rubber ◽  
Truck Tires ◽  
Basic Work ◽  
Isoprene Rubber ◽  
Research Institute

Abstract Years of research at the S. V. Lebedev All-Union Scientific Research Institute for Synthetic Rubber have provided industry with a number of methods for making synthetic rubber from isoprene. Of all the known synthetic rubbers this comes closest to natural rubber in structure and properties; it is the best available substitute of natural rubber, possessing a high degree of elasticity and strength. The present article is a brief summary of the basic work on isoprene rubber done by the Scientific Research Institute of the Tire Industry. On the basis of this work recommendations were made for the development of the production of synthetic isoprene rubber and the substitution of isoprene rubber for natural rubber in the manufacture of heavy duty truck tires. By using different polymerization processes it is possible to produce isoprene rubbers whose chain structures are very similar, but whose molecular weights, and therefore physical and technological properties, are very different. The cis structure of the 1,4 polyisoprene chains is the basic structural element of the new isoprene polymer. Therefore these synthetic isoprene rubbers (SKI) obtained through catalytic polymerization when vulcanized show a crystalline structure when x-rayed in the stretched state. The x-ray photographs also show that the geometric distribution of interference spots in SKI rubbers corresponds to the distribution of interference spots in natural rubber, but that the relative intensities of the crystalline, liquid, and amorphous scatterings in the two rubbers are different (Figure 1).

Rubber Oxidation and Aging Studies Safe Limits of Sample Thickness

1951 ◽  
Vol 24 (4) ◽  
pp. 999-1016
Author(s):  
George W. Blum ◽  
J. Reid Shelton ◽  
Hugh Winn
Keyword(s):  
Natural Rubber ◽  
Accelerated Aging ◽  
Sample Thickness ◽  
Oxygen Absorption ◽  
Absorption Data ◽  
Synthetic Rubber ◽  
Constant Rate ◽  
Aging Studies ◽  
Safe Limits ◽  
Natural Rubber Vulcanizates

Abstract Safe limits of sample thickness for rubber oxidation and aging studies, such that the chemical reaction rather than the rate of diffusion will be rate-controlling have been investigated for natural-rubber vulcanizates and for four synthetic-rubber types. For studies involving the entire range of oxidation, including the autocatalytic stage of rapid oxygen absorption, the conventional 0.075-inch thickness is frequently not satisfactory for accelerated aging and oxidation studies if it is desired to avoid limitation by diffusion. Only in the GR-S black stock was this thickness found to be satisfactory up to a temperature of 100° C. The other stocks, including natural rubber, Butaprene-NXM, and Neoprene black and gum stocks all require thinner samples to ensure that the observed rate of oxygen absorption is free of limitation by diffusion. A method of calculating the probable limiting value of sample thickness, above which the rate of oxidation in the autocatalytic stage is limited by diffusion, has been developed on the basis of volumetric oxygen absorption data obtained with GR-S. The method has also been applied to natural-rubber vulcanizates and to other synthetic-rubber types to locate the approximate limiting values at various temperatures for oxidation and aging studies which extend into the autocatalytic stage of rapid reaction. The constant-rate period of oxidation is more important from a practical point of view than the autocatalytic stage, since properties are so seriously degraded as to make the rubber of little value before it reaches the final stage of rapid oxidation. Somewhat thicker samples may be used for studies that are confined to the earlier stages of oxidation. A 0.075-inch sample is free of limitation by diffusion in the constant-rate stage in the following cases: GR-S black and gum stocks at 110° C; Hevea black with added antioxidant at 100° C; and uninhibited Hevea black and gum stocks at 60° C. A 0.040-inch sample is satisfactory in this range for: uninhibited Hevea black at 100° and gum at 80° C; Butaprene-NXM black at 100° and gum at 90° C; and Neoprene black and gum stocks at 100° C.

Properties of Ebonite. XXXVII. Electrical Properties of Synthetic Rubber Ebonites

1949 ◽  
Vol 22 (4) ◽  
pp. 1084-1091
Author(s):  
D. G. Fisher ◽  
L. Mullins ◽  
J. R. Scott
Keyword(s):  
Natural Rubber ◽  
Power Factor ◽  
Power Loss ◽  
Ionic Conduction ◽  
Effect Of Temperature ◽  
Plastic Yield ◽  
Styrene Copolymers ◽  
Synthetic Rubber ◽  
High Dielectric ◽  
Butadiene Styrene

Abstract Experiments were carried out to explore the possibility of making good electrical ebonites from various types of synthetic rubber. The ebonites produced were tested for permittivity and power factor over wide ranges of temperature and frequency. Thioplasts (Thiokols AZ and FA) apparently do not produce hard ebonitelike vulcanizates by the normal procedure. Neoprenes (GN and I) give ebonites, but with such high dielectric power loss as to be unsuitable for use as high-frequency dielectrics; moreover, if the mix contains zinc oxide, the ebonite has a very hygroscopic and therefore electrically unsatisfactory surface. Butadiene copolymers containing polar groups (butadiene-acrylonitrile types and Thiokol RD) give ebonites with high power loss, hence are not suitable for making high-grade electrical ebonites. Polybutadiene (Buna-85) and butadiene-styrene copolymers (GR-S, Hycar-EP, Buna-S) are much nearer to natural rubber as far as the radio-frequency (100 to 2,500 kc. per sec.) power loss of their ebonites is concerned. The GR-S ebonite examined was not so good as natural rubber at room temperature, but was superior above about 50° C. Buna-85 and Hycar-EP were superior to natural rubber over the whole temperature range; indeed, the high-styrene copolymers, as represented by Hycar-EP and Buna-SS, appear to be the best type of synthetic rubber for making ebonite with low power loss, especially at high frequencies and temperatures. The effects of changing temperature and frequency on permittivity and power factor are discussed. Attention is drawn to the big effect of temperature on power factor; this was less with polybutadiene and butadiene-styrene ebonites than with natural rubber ebonite, in keeping with the greater heat resistance of the former as judged by plastic yield tests. Comparison of the effects of rising temperature and decreasing frequency shows that these produce broadly similar effects on power factor, as would be expected on theoretical grounds, but that rising temperature superposes a second effect (an increase), presumably due to increased ionic conduction.

The Dynamic Characteristics of Neoprene Vulcanizates

1949 ◽  
Vol 22 (2) ◽  
pp. 450-464 ◽  
Author(s):  
N. L. Catton ◽  
E. H. Krismann ◽  
W. N. Keen
Keyword(s):  
Natural Rubber ◽  
Dynamic Characteristics ◽  
Dynamic Properties ◽  
Complete Solution ◽  
Practical Application ◽  
Testing Methods ◽  
Synthetic Rubber ◽  
Engineering Data ◽  
Rubber Part ◽  
Vibration Problems

Abstract The utilization of the elastomeric spring goes back at least to the days of solid rubber carriage tires. The use of such materials to dampen vibration or absorb shock expanded rapidly despite the lack of engineering data and the inadequacy of testing methods for proper evaluation. Within the last twenty years these materials have been used in many dynamic applications, even though no appropriate means existed for the measurement of dynamic properties to determine their suitability for the particular service. Coincident with the practical application of rubber parts to vibration problems, engineers developed considerable data on the use of natural rubber in springs. Marked differences in performance were encountered when engineers were obliged to replace natural rubber with synthetic rubber in spring applications. Some engineers redesigned the rubber part used and obtained workable, although not entirely acceptable, performance. Design alone was not a complete solution to the problem, and it was necessary to call on the rubber technologist to produce vulcanizates having properties especially suitable for dynamic service.

Science and Technology of Reclaimed Rubber

1967 ◽  
Vol 40 (1) ◽  
pp. 217-237 ◽  
Author(s):  
D. S. le Beau
Keyword(s):  
Natural Rubber ◽  
Polymer Processing ◽  
Raw Material ◽  
Plastic State ◽  
Substantial Part ◽  
Process Conditions ◽  
Fibrous Materials ◽  
The Past ◽  
Synthetic Rubber ◽  
Mechanical Handling

Abstract Developments in the rubber reclaiming industry are closely related to those in the rubber industry in general. The vulcanized rubber produced by the latter becomes in time the raw material used by the former. Although not superficially obvious, there has been considerable change in the reclaiming industry in the past two decades, required by the introduction of large proportions of synthetic rubber. Since this occurs both alone and in blends with natural rubber, reclaiming of SBR had to be studied in detail so that processes could be adjusted to give approximately the same viscosity from synthetic rubber and from natural, retaining existing procedures for fiber removal and mechanical handling as much as possible. It would have been economically impossible for reclaimers to use any process which required segregation and separate disposal of a substantial part of their raw material. The machinery used in the production of reclaim, and the reclaiming processes used today, are for the major part still the same as used before. The object of reclaiming vulcanized scrap is still the same, i.e., the breakdown (depolymerization) of the scrap to a plastic state which will permit reuse of it in the current rubber processing machinery for the manufacture of new goods. This breakdown is achieved by the application of energy. The type of energy is fundamentally irrelevant, but economics today dictate that it be heat, with partial exclusion of the oxidizing atmosphere, and therefore most of today's reclaim production is carried out in steam. One new continuous reclaiming process was developed during the last fifteen years which relies on electric energy to provide the necessary heat and working of the vulcanized scrap. A fundamental change in requirements of reclaim was also brought about once the synthetic rubber production had proceeded to the point where it was commercially possible to assign more detailed specifications which described the polymer processing behavior limits—a feat not previously achieved for commercial natural rubber. This type of specification was carred over to a considerable extent into the production and sale of today's reclaim. All in all, the extensive research and polymer knowledge which were acquired for the successful production of synthetic rubber have resulted in a much greater control in the production of reclaim and a much greater understanding of the reactions occurring in polymers during reclaiming. Because vulcanized scrap usually contains extraneous material (fiber) which must be removed during reclaiming the process conditions have in the past been selected primarily to accomplish this removal and were not those best suited for the actual reclaiming reaction. Progress has been made during these last years in removing the fibrous materials before reclamation, thereby permitting conditions in the devulcanization cycle to be determined by the actual needs of the vulcanized scrap.

Sign in / Sign up

Export Citation Format

Share Document