Word: methyl
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Dates: during 1940-1949
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Closely related to it is isoprene (also called methyl butadiene). Although isoprene is the basic unit in natural rubber, it is useless by itself. But when isobutylene and isoprene are polymerized together the result is Standard Oil's butyl, tough, very elastic, now favored for inner tubes. It is to be made at a rate of 100,000 tons a year...
Solutions thus treated acquire the various characteristics of a natural blood serum which would be obtained from an animal immunized with the same antigen. The Caltech researchers have already prepared antibodies against a few simple chemical antigens (e.g., methyl blue), and are working toward more complex antigens such as snake venoms and viruses...
Natural rubber can be thought of as a long hydrocarbon chain, composed essentially of a cramped-up chain of molecules of methyl butadiene or isoprene. When the rubber is stretched this chain unfolds; when the rubber contracts, it doubles up again. So the problem of synthesizing rubbers is 1) to find basic chain-units similar to methyl butadiene, 2) to build these up into larger, stringy, stretchy molecules. Best way of classifying synthetic rubbers is by their basic materials...
...most synthetic rubbers. Butadiene molecules were first polymerized-or built up into larger molecules-with the help of metallic sodium, making a stretchy substance which its German inventors about 1927 called Buna (Bu for butadiene, Na for sodium). It was not a very satisfactory synthetic: but better than the methyl rubber (dimethyl butadiene) of World War I, when it was said German Army trucks often had to be jacked up overnight so that their solid tires would not flatten out permanently under their weight. German chemists soon discovered ways to make superior products by combining butadiene with other substances...
Entomologists have occasionally found ancient insects beautifully preserved in hunks of amber, which is fossilized natural resin. It occurred to Dr. Sando that if a suitable substance could be found, the same sort of thing could be done deliberately. After much experiment he chose Plexiglas, a mixture of monomers (methyl methacrylate, ethyl methacrylate, etc.) which hardens into a glassy plastic. In blocks of this stuff he immured small dead frogs, a tarantula, the bones of a human hand (see cuts); a rattlesnake's head, complete with fangs, a peacock feather, an iridescent butterfly, a garter snake, flowers, ears...