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Let's introduce a new and important chemical concept
Dr. Eugene Rochow observed the catalytic action of copper metal..
General Electric did take one action with Rochow's first methyl silicones. They filed patents, differentiating them in their patent claims from the ethylphenyl silicones made at Corning. These patents led to a controversy between the two companies; Corning, having introduced their silicone work to GE, then sued GE in the patent courts claiming GE's methyl silicone were obvious in light of Corning's own work. Corning lost, the methyl silicones became GE's sole property.
Observation and Science
of observation serve science well. See Aeneas the King,
here struck by an arrow. Victory and defeat, the founding
of Rome, hang in the balance. You might read of a victory
for observation from Virgil's Aeneid, Book XII, lines
Heat and Chemical
Resistant Silicone Rubber
Eugene Rochow set out to make methylsilicone polymer. This is what chemists do.
Rochow reacted (9) with water just as Hyde had done with (7). He obtained sticky fluids. But when he heated them, they hardened to clear, resinous materials, certainly methylsilicones of the structure shown below:
But Dr. Rochow needed a better method to make the methylsilicones - some pathway that could be converted to a low cost, commercial process. Successful chemists think by analogy. Dr. Rochow remembered the work of Dr. Alfred Stock, in Germany. Stock believed that a H- atom attached to silicon was just the first member of a like-behaving series of alkyls: CH3-, C2H5-, etc.
Rochow knew that he could make trichlorosilane, HSiCl3, by reacting:
2Si + 6HCl --> 2HSiCl3 + 2H2
Suppose he reacted silicon with methyl chloride, CH3Cl. He would expect to obtain CH3SiCl3, right? If so, could he adjust the ratio of Si and CH3Cl and obtain the critical intermediate to methyl silicones, (CH3)2SiCl2?
He found a pool of liquid in the cooled flasks (on the right in the sketch) and treated the liquid with water. "The end result is a clear, resinous body I believe is methyl silicone," Rochow wrote in his laboratory notebook late that night. The chemical reaction to make (9) was a simple one:
2CH3Cl + Si --> (CH3)2SiCl2 (9)
You may remember (or you will learn) that a catalyst participates in a chemical reaction by lowering the activation energy for the chemical reaction. Activation energy is the energy required to form the "activated complex" through which all chemical reactions must go on the pathway from starting materials to products. Lowering the activation energy increases the rate of a chemical reaction at any specific temperature - it allows reactions to proceed at practical rates at lower temperatures than without the catalyst.
When Rochow added the water, he made his methyl silicone:
n(9) + nH2O --> n[(CH3)2SiO]n + nHCl
In 1940, Eugene Rochow demonstrated a one step method to make silicone polymers. Much more would need to be done to make Rochow's process practical for the manufacture of high-temperature insulation.
Science and Mathematics
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