Synthetic rubbers, development

This has the distinction of being the first synthetic rubber developed and commercially produced in the USA. It was also clearly the invention of Dr. J. C. Patrick, who not only discovered this polymer, but also founded the company, Thiokol Corporation, to produce and market it. 

The revolutionary development of stereospecific polymerization by the Ziegler-Natta catalysts also resulted ia the accomplishment ia the 1950s of a 100-year-old goal, the synthesis of i7j -l,4-polyisoprene (natural mbber). This actually led to the immediate termination of the U.S. Government Synthetic Rubber Program ia 1956 because the technical problem of dupHcating the molecular stmcture of natural mbber was thereby solved, and also because the mbber plantations of the Far East were again available. 

Rubber and Elastomers Rubber and elastomers are widely used as lining materials. To meet the demands of the chemical indus-tiy, rubber processors are continually improving their products. A number of synthetic rubbers have been developed, and while none has all the properties of natural rubber, they are superior in one or more ways. The isoprene and polybutadiene synthetic rubbers are duphcates of natural. 

The brittleness of isotactic polystyrenes has hindered their commercial development. Quoted Izod impact strengths are only 20% that of conventional amorphous polymer. Impact strength double that of the amorphous material has, however, been claimed when isotactic polymer is blended with a synthetic rubber or a polyolefin. 

The first use of butadiene to make synthetic rubber was demonstrated in Russia in 1910 by S.V. Lebchev, who also developed a synthesis of butadiene from ethanol obtained by fermentation. 

Nobel did well in the dynamite business and eventually opened 90 factories and laboratories in more than 20 countries. By the time of his death in 1896, he held 355 patents—not only for explosives, but also for developing synthetic rubber, leather, and silk. Upon his passing, Nobel left instructions that his considerable fortune be used to award an annual prize to scientists and others who... 

Neoprene, Carothers first practical invention, was made reluctantly, as a kind of side issue to his scientific investigation of polymers. Synthetic rubber was of great commercial interest. The car-happy United States used half the world s natural rubber, and demand had outstripped the supply from wild rubber trees in the Amazon. Price fluctuations on British rubber plantations in Southeast Asia provided further incentive for the development of synthetic substitutes. Du Pont had been trying without success to... 

Surprisingly, the idea that Collins new compound might form the basis for a synthetic rubber took several weeks to evolve. And it was not Carothers, but Stine s successor, Elmer K. Bolton, who first realized that the molecular structure of Collins mass was similar to that of isoprene, the main constituent of natural rubber. Bolton had studied in Germany and was familiar with its World War I efforts to develop an ersatz rubber for tires. 

Ever since World War II spurred the development of technological advances such as radar, synthetic antimalarials, and synthetic rubber, our nation s strengths... 

Since its recognition and systematic exploration by Otto Diels and Kurt Alder in the 1920s, the Diels-Alder reaction motif (5.84b) has provided one of the most powerful tools of organic synthesis. The Diels-Alder reaction led directly to the dramatic pre-World War II development of the chemical industry for production of synthetic rubber and other polymeric materials. Today, the commercial impact of Diels-Alder methods extends to virtually all areas of agricultural, pharmaceutical, and natural-products chemistry. 

Buna [Butadien natrium] The name has been used for the product, the process, and the company VEB Chemische Werke Buna. A process for making a range of synthetic rubbers from butadiene, developed by IG Farbenindustrie in Leverkusen, Germany, in the late 1920s. Sodium was used initially as the polymerization catalyst, hence the name. Buna S was a copolymer of butadiene with styrene Buna N a copolymer with acrylonitrile. The product was first introduced to the pubhc at the Berlin Motor Show in 1936. Today, the trade name Buna CB is used for a polybutadiene rubber made by Bunawerke Hiils using a Ziegler-Natta type process. German Patent 570, 980. 

IG IG-Farbcnindustric in Germany developed many processes before World War n, but the one most associated with its name is probably the Aldol process for making butadiene for synthetic rubber. The name has been used also for the Bergius-Pier process. 

Hermann Staudinger, on developing a new and simple preparation of the monomer, studied the polymerization of isoprene as early as 1910 (42). Stimulated by the differences in physical properties between his synthetic rubber and natural rubber, he turned his full attention to the study of polymers. 

I, too, was caught up in the wave of enthusiasm for this new science which had the lofty goal of relating the properties of materials to their molecular structure, and, in the end, to "tailor-making molecules for specific properties. Since one of the big developments at that time was the newly-started synthetic rubber programs of the American and Canadian governments, I chose the topic of the emulsion copolymerization of butadiene-styrene as the subject of my doctoral dissertation. 

Whereas, at the beginning of the thirties, polystyrene had been the driving force in the styrene monomer and polystyrene fields, this development was soon reversed. Under Germany s efforts to become self-sufficient there was a much bigger demand for styrene monomer for the manufacture of synthetic rubber than for polystyrene. As early as 1938 approximately 2500 t of styrene monomer was produced in Ludwigshafen for the newly commissioned rubber plants. When the Allies were cut off from their Asian rubber plantations in the Second World War, the U.S.A. followed suit with large styrene monomer capacities for the manufacture of rubber. Thus there were big capacities for styrene monomer available by 1945 for other uses. 

All petrochemical projects, either planned or under construction, are large-scale plants of international proportions. When completed, the Chinese hope to develop the capacity to manufacture a wide variety of general-use plastics, synthetic rubber, synthetic textiles and other petrochemical-derived products. 

During World War II, the Japanese cut ofFU.S. access to sources of natural rubber, giving the Americans a strategic imperative to develop and expand the manufacture of synthetic rubber. The C4 streams in refineries were a direct source of butadiene, the primary synthetic rubber feedstock. As a coincidence, the availability of this stream was growing rapidly with the expansion of catalytic cracking to meet wartime gasoline needs. Additional butadiene was manufactured by dehydrogenation of butane and butylene also. 

The Government Rubber Reserve Company in the 1940s pioneered the development of styrene-butadiene copolymers, by far the largest volume of synthetic rubber used today. Now usually known as SBR, it has also been called Buna-S, Rzrtadiene with a sodium (Na) catalyst and copolymerized... 

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