The Determination of Unsaturation in Butadiene Synthetic Rubber

1948 ◽  
Vol 21 (4) ◽  
pp. 830-834
Author(s):  
P. P. Kobeko ◽  
E. K. Moskvina
Keyword(s):  
Carbon Tetrachloride ◽  
Natural Rubber ◽  
Carbon Disulfide ◽  
Addition Product ◽  
Butadiene Rubber ◽  
Synthetic Rubber ◽  
Iodine Chloride ◽  
Hydrolysis Of

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.

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
Keyword(s):  
Natural Rubber ◽  
Chemical Properties ◽  
Experimental Results ◽  
Butadiene Rubber ◽  
Synthetic Rubber ◽  
Iodine Chloride

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.

A New Method for the Direct Determination of Rubber. A Preliminary Communication

1938 ◽  
Vol 11 (2) ◽  
pp. 438-438
Author(s):  
E. Kheraskova ◽  
E. Korsunskaya
Keyword(s):  
Acetic Acid ◽  
Natural Rubber ◽  
Direct Determination ◽  
Methyl Groups ◽  
Butadiene Rubber ◽  
Double Bonds ◽  
Synthetic Rubber ◽  
Oxidation Of Organic Compounds ◽  
Preliminary Communication

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.

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.

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.

Quantitative Determination of Copper in Natural Rubber

1953 ◽  
Vol 26 (1) ◽  
pp. 251-256 ◽  
Author(s):  
Lewis T. Milliken
Keyword(s):  
Carbon Tetrachloride ◽  
Natural Rubber ◽  
Quantitative Determination ◽  
Oxidation Process ◽  
Aqueous Suspension ◽  
Wet Oxidation ◽  
Acid Extract ◽  
Organic Solution ◽  
Determination Of Copper

Abstract A procedure is recommended in which small amounts of copper in rubber can be measured quantitatively by determining the depth of color of a copper carbamate complex in a carbon tetrachloride solution. The complex is formed in an alkaline solution prepared from an acid extract of the rubber ashed at 550° C. This procedure yields results which are as reliable as those obtained by the more tedious and time-consuming procedures involving the wet-oxidation process which are at present recommended by standardizing organizations. The use of an organic solution rather than an aqueous suspension gives better reproducibility, permits easier use of a photometer, and reduces the interference due to iron by a factor of ten.

Sulfur Bond in Vulcanizates Implications of Halogen Reactions

1947 ◽  
Vol 20 (3) ◽  
pp. 627-648
Author(s):  
S. R. Olsen ◽  
C. M. Hull ◽  
Wesley G. France
Keyword(s):  
Double Bond ◽  
Carbon Tetrachloride ◽  
Sulfur Atom ◽  
Side Reactions ◽  
Double Bonds ◽  
Vulcanized Rubber ◽  
Iodine Chloride ◽  
Allyl Sulfide ◽  
Sulfur Bond

Abstract 1. When iodine chloride is used for the determination of double bonds in sulfur-vulcanized rubber or GR-S, it undergoes side reactions induced by combined sulfur. 2. Bromine in carbon tetrachloride is believed to give a satisfactory measure of the double bonds in a rubber-sulfur vulcanizate dissolved in dichlorobenzene-chloroform mixture. 3. The relation of one double bond consumed per sulfur atom combined in the rubber-sulfur type vulcanizate was confirmed. 4. Organic accelerators (in the absence of metal activators) catalyze the combination of sulfur without altering the ratio of one double bond loss per sulfur atom combined. 5. The introduction of a metal oxide or soap, such as zinc, causes a different type of vulcanization, which results in less than one double bond consumed per sulfur atom combined. 6. The reactions of propyl sulfide, dodecyl sulfide, propyl disulfide, allyl sulfide, methallyl sulfide, and butylmethallyl sulfide with iodine chloride and with bromine, respectively, are described. 7. The behavior of rubber-sulfur vulcanizates resembles that of butylmethallyl sulfide in reactions with iodine chloride and bromine, respectively; this suggests an alkyl-allyl type sulfur bond. 8. The theory of vulcanization proposed by Armstrong, Little, and Doak, based on the α-methylenic concept of Farmer, is supported by the findings of this investigation.

scholarly journals Study of the Mechanical Properties of Natural Rubber Composites with Synthetic Rubber Using Used Cooking Oil as a Softener

2020 ◽  
Vol 20 (5) ◽  
pp. 967
Author(s):  
Nasruddin Nasruddin ◽  
Tri Susanto
Keyword(s):  
Mechanical Properties ◽  
Natural Rubber ◽  
Butadiene Rubber ◽  
Rubber Composites ◽  
Cooking Oil ◽  
Used Cooking Oil ◽  
Synthetic Rubber ◽  
Natural Rubber Composites ◽  
Automatic Heat ◽  
The Difference

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.

scholarly journals Mechanical and morphology characteristics of natural rubber-styrene butadiene rubber (NR-SBR) blends in the presence of natural microbentonite

2021 ◽  
Vol 912 (1) ◽  
pp. 012072
Author(s):  
B Wirjosentono ◽  
A H Siregar ◽  
D A Nasution
Keyword(s):  
Natural Rubber ◽  
Rubber Tree ◽  
Weight Ratio ◽  
Styrene Butadiene Rubber ◽  
Butadiene Rubber ◽  
Mineral Oils ◽  
Synthetic Rubber ◽  
Styrene Butadiene ◽  
Morphology Characteristics ◽  
Xylene Solution

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.

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