Natural Vs Synthetic Rubber
Natural rubber, coming from latex, is mainly poly-cis-isoprene containing traces of impurities. Although it exhibits many excellent properties, natural rubber is often inferior to synthetic rubbers, especially with respect to its thermal stability and its compatibility with petroleum products.
Synthetic rubber is made by the polymerization of a variety of petroleum-based precursors called monomers. The most prevalent synthetic rubbers are styrene-butadiene rubbers (SBR) derived from the copolymerization of styrene and 1,3-butadiene. Other synthetic rubbers are prepared from isoprene (2-methyl-1,3-butadiene), chloroprene (2-chloro-1,3-butadiene), and isobutylene (methylpropene) with a small percentage of isoprene for cross-linking. These and other monomers can be mixed in various proportions to be copolymerized to produce products with a range of physical, mechanical, and chemical properties. The monomers can be produced pure and the addition of impurities or additives can be controlled by design to give optimal properties. Polymerization of pure monomers can be better controlled to give a desired proportion of cis and trans double bonds.
Read more about this topic: Synthetic Rubber
Famous quotes containing the words natural, synthetic and/or rubber:
“The open frontier, the hardships of homesteading from scratch, the wealth of natural resources, the whole vast challenge of a continent waiting to be exploited, combined to produce a prevailing materialism and an American drive bent as much, if not more, on money, property, and power than was true of the Old World from which we had fled.”
—Barbara Tuchman (1912–1989)
“In every philosophical school, three thinkers succeed one another in the following way: the first produces out of himself the sap and seed, the second draws it out into threads and spins a synthetic web, and the third waits in this web for the sacrificial victims that are caught in it—and tries to live off philosophy.”
—Friedrich Nietzsche (1844–1900)
“First, are you our sort of a person?
Do you wear
A glass eye, false teeth or a crutch,
A brace or a hook,
Rubber breasts or a rubber crotch,
Stitches to show something’s missing?”
—Sylvia Plath (1932–1963)