Reactions of Iodine, Iodine Chloride and Thiocyanogen with the Hydrocarbons of Natural Rubber and Synthetic Rubber

1945 ◽  
Vol 18 (1) ◽  
pp. 24-31
Author(s):  
P. I. Medvedchuk ◽  
F. D. Aldoshin ◽  
V. P. Marovich ◽  
A. V. Repman

Abstract The reactions of iodine, iodine chloride and thiocyanogen with solutions of natural rubber and of synthetic sodium-butadiene rubber were studied. The experimental results show that the chemical properties of these two hydrocarbons are in general similar, although there are also certain differences which can be explained by the peculiarities of their structures. The products of the reactions of iodine chloride and of thiocyanogen with natural rubber and sodium-butadiene rubber were isolated, and their compositions and some of their properties are described.

1948 ◽  
Vol 21 (4) ◽  
pp. 830-834
Author(s):  
P. P. Kobeko ◽  
E. K. Moskvina

Abstract 1. It has been found that synthetic rubber does not precipitate from a solution of dichloromethane by the addition of Wijs reagent, whereas natural rubber does precipitate under the same conditions. The reverse relation occurs with carbon disulfide as solvent. 2. A method has been developed for the determination of the unsaturation of butadiene rubber in solution in dichloromethane by the use of Wijs reagent. 3. It has been demonstrated that, by the use of a solution of iodine chloride in carbon tetrachloride, the reaction with rubber is complicated by the hydrolysis of iodine chloride during titration, but not by the substitution of hydrogen by halogen nor by the hydrolysis of the rubber-halogen addition product. 4. The possibility of obtaining accurate values for unsaturation by a calculation of this hydrolysis is demonstrated. 5. Two methods have been developed for the determination of the unsaturation of natural and butadiene rubbers.


2017 ◽  
Vol 44 (5) ◽  
pp. 25-28 ◽  
Author(s):  
A.A. Zuev ◽  
L.R. Lyusova ◽  
N.P. Boreiko

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.


1929 ◽  
Vol 2 (3) ◽  
pp. 441-451 ◽  
Author(s):  
Thomas Midgley ◽  
Albert L. Henne

Abstract Two hundred pounds of pale crepe rubber have been destructively-distilled at atmospheric pressure. The distillate was fractionated and its components identified from C5 to C10, as shown in the table. Assuming that the Staudinger formula is correct, that the single bonds furthest from the double bonds are the weaker spots and that the formation of six-carbon rings is favored, it has been shown that nearly all of the compounds actually isolated could be predicted. The experimental results, together with forthcoming experimental data, are expected to be used to throw light upon the formula of the rubber molecule.


2020 ◽  
Vol 20 (5) ◽  
pp. 967
Author(s):  
Nasruddin Nasruddin ◽  
Tri Susanto

This research aims to study the mechanical properties of natural rubber composites with nitrile butadiene rubber and ethylene propylene diene monomer rubber. Composite fillers consisted of kaolin, and softener using used cooking oil. The study was carried out by the method of mastication, vulcanization, and maturation of the compound into rubber vulcanizates. The vulcanization and mastication process is carried out in the open mill. The maturation of the compound into rubber vulcanizates from the results of mastication and vulcanization was carried out using semi-automatic heat press and press at a temperature of 130 °C ± 2 °C for 17 min. Based on data from testing the mechanical properties of five samples from five formulas, the mechanical properties of composite rubber are affected by the ratio of natural rubber, synthetic rubber, kaolin, and used cooking oil as a softener. The difference in the results of vulcanizates rubber testing of natural rubber composites with synthetic rubber is not only influenced by the ratio of the composite, but also by the degree of cross-linking between the material molecules.


2021 ◽  
Vol 912 (1) ◽  
pp. 012072
Author(s):  
B Wirjosentono ◽  
A H Siregar ◽  
D A Nasution

Abstract Natural rubber (NR) has been the world renewable natural elastomer produced mainly in South East Asia from the sap of rubber tree (hevea brasiliensis). However it only exported to manufacturing countries for production of various engineering and specialty rubber products. Blending of the natural rubber with synthetic rubber such as styrene butadiene rubber (SBR) is a mean to improve engineering specification of the NR, especially due to exposure of mineral oils during its service life. Whereas natural microbentonite functions not only as filler but also as coagulant breaker in both SIR-10 and SBR matrices, which improves miscibility of the blends. In this work blending of Indonesian natural rubber (NR: SIR-10) with styrene butadiene rubber (SBR) were carried out in reflux reactor in xylene solution in the presence of various loading of natural microbentonite as fillers. Miscibility of the blends were measured from their mechanical properties as well as morphology of their fracture surfaces using electron microscopy (SEM). It was found that optimum loading of microbentonite in the NR/SBR (weight ratio: 50/50) blend was 3 per hundred rubber (phr), which showed good adhesion of the rubber matrices onto the filler surface and without any agglomeration.


1944 ◽  
Vol 17 (3) ◽  
pp. 719-730
Author(s):  
J. R. Scott

Abstract The experiments described here were designed to examine the properties of ebonites made from various kinds of Buna synthetic rubber, including Buna-85, Buna-115, Buna-S and Buna-N. All Bunas are said to form ebonites by vulcanization with the normal amount of sulfur, Buna-85 and Buna-115 giving the best products. The resulting ebonites are stated to have much higher plastic yield temperatures than ordinary ebonite, figures quoted ranging from 100° to 175° C by the Martens test, compared with 70° to 90° C for natural-rubber ebonites. It may be added that Russian butadiene rubber likewise is claimed to give ebonites with much higher yield temperatures, namely, up to 160° C by a Vicat needle test, than ordinary ebonites, which give about 93° C. On the other hand, Buna ebonites are relatively brittle. The electrical properties of these ebonites are said to be good, and in this connection it should be noted that soft vulcanizates made from Buna-85 and Buna-115 have lower power factors than those made from natural rubber. Buna ebonites are more resistant than ordinary ebonite to attack by chemicals and to the swelling action of liquids such as benzene and nitrobenzene. The present report deals with certain properties of Buna ebonites, viz., plastic yield, cross-breaking strength, impact strength, radio-frequency permittivity and power factor.


2016 ◽  
Vol 851 ◽  
pp. 117-121
Author(s):  
Pran Hanthanon ◽  
Thiti Kaisone ◽  
Chanon Wiphanurat ◽  
Tarinee Nampitch

A blend of natural rubber (NR) and styrene butadiene rubber (SBR) was tested against conventional rubber products sold in department stores and markets, using nuclear magnetic resonance (NMR) spectroscopy to measure the amount of natural or synthetic rubber in the product. 1H-NMR spectroscopy was employed for the rubber blend and 13C-NMR spectroscopy for conventional products. The chemical shift of all the samples from the structure of natural rubber (cis-1,4 polyisoprene) was observed.


2015 ◽  
Vol 1119 ◽  
pp. 324-328
Author(s):  
Mazlina Mustapha Kamal

Much published literature on the way in which phase morphology and filler distribution affect blend properties is contractor or confusing The blending of two or more polymers by physical or chemical means may improve a variety of physical and chemical properties of the constituent polymers. The effect of different modes of filler addition on dispersion and viscosity of Epoxidisd Natural Rubber (ENR) and cis 1,4 –polybutadiene rubber (BR) has been studied. Experiments were carried out to elucidate the relationship and to determine whether the use of special mixing technique and compatabilizers might have a beneficial effect on Epoxidised Natural Rubber: Butadiene Rubber (ENR:BR) blend properties. The findings indicated blending times for combining Silica, BR and ENR was rather difficult even a close viscosity of each rubber was applied. Results indicated a high degree of compatibility with fine structured blends being quickly and easily produced with compound containing compatibilizer than compound with any. Hence, a high viscosity and poor filler dispersion was obtained with all mixing techniques applied except with the one with the coupling agent.


1938 ◽  
Vol 11 (2) ◽  
pp. 438-438
Author(s):  
E. Kheraskova ◽  
E. Korsunskaya

Abstract The conventional methods for the direct determination of rubber cannot be used for determining natural rubber in the presence of sodium-butadiene rubber. These methods are based either on precipitation of the rubber from solution or on the determination, by one method or another, of the double bonds in the rubber molecule. Since natural rubber and synthetic rubber differ in their solubilities but little, the method of precipitation obviously cannot be used for their separation. Nor are methods which involve determining the double bonds adequate to distinguish them, because both kinds of rubber are unsaturated compounds. It was therefore of interest to develop a method of analysis based on the determination of the methyl groups, which are present only in the natural rubber molecule. Kuhn and L'Orsa (Z. angew. Chem., 44, 847 (1931)) have shown that, in the oxidation of organic compounds, a methyl group connected with a carbon atom is partially oxidized to acetic acid. The object was to develop this reaction into a method of rubber analysis by establishing the optimum conditions for the quantitative oxidation to acetic acid of all the methyl groups in the rubber hydrocarbon.


2021 ◽  
Vol 11 (1) ◽  
pp. 22-26
Author(s):  
Abdulaziz K Bubshait

The Butadiene is a raw material used in the petrochemical industry. The use of Butadiene has risen with petrochemical market growth. The Global market is forecasting a demand growth for butadiene applications, especially for rubber materials. The estimated synthetic rubber market is $19.1 billion in 2021 and forecasted to reach $23.2 billion in five years. The dynamic growth in butadiene applications will introduce new products used in many things from the food industry to sports and goods. Also, the rubber materials have different applications in the automotive industry, oil and gas, medical products, and plastics. Companies’ strategic planning to increase the production of synthetic rubber for the global market. The demand increased as new applications were introduced to the market. The stability of oil prices will have the rubber market steady which always leads to optimal pricing. The diver for Butadiene rubber applications is to maximize production by having different kind of materials that applied for several products. The global business development indicated the ability to increases the synthetic rubber market rubber and capacities, which will enhance the chemical process techniques, new technology design, and efficiency that will maximize production and minimize product cost. Looking into the price difference between synthetic and natural rubber, many fluctuation variables were introduced in the price of each type. For example, synthetic rubber price is high, depending on crude oil, natural gasoline and naphtha prices, since those feedstocks are fed to the cracking units, as C4 is one of the cracking products. Therefore, any change in the oil prices will influence the butadiene price, which is the feed for most rubber plants. In addition, the utilities required for those plants to operate have a major impact on overall price. On the other hand, Natural rubber is an agricultural product and dependent on soil type and weather.


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