Synthetic Rubber From Butadiene and Styrene

In the 1930s, a wide range of hydrogenation and dehydrogenation processes was already developed by companies in the petroleum industry to increase gasoline yield. Olefins had been used to provide polygasoline and alkylates, as well as many other petrochemical intermediates. A form of synthetic robber had been 

Nine dehydrogenation plants were eventually authorized by the Rubber Reserve Compaity to make 330,000 tonnes year of butadiene. Two were based on butane and seven on butene. During construction of these plants it was also deeided to make about 220,000 tonnes.year of butadiene by toe Russian Lebedev process based on ethanol  

Little is known about toe Lebedev process, which was developed in Russia in 1927 during toe investigation of synthetic rubber produetion. It was a one-step proeess that converted ethanol to butadiene by simultaneous dehydrogenation, dehydration, and condensation stages  

The catalyst used was nominally a mixture of 75% magnesia and 25% silica or sihceous earth, which are well known as dehydrogenation and dehydration catalysts respectively. Up to 3% chromium oxide was included to inhibit toe formation of magnesium silicate. 

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Redox polymerizations are usually carried out in aqueous solution, suspension, or emulsion rarely in organic solvents. Their special importance lies in the fact that they proceed at relatively low temperatures with high rates and with the formation of high molecular weight polymers. Furthermore, transfer and branching reactions are relatively unimportant. The first large-scale commercial application of redox polymerization was the production of synthetic rubber from butadiene and styrene (SBR1500) at temperatures below 5 °C (see Example 3-44). 

Emulsion polymerisation was initially developed for producing synthetic rubber from butadiene and styrene during the Second World War. The system... 

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