Tires to Lemons – Well, Not Exactly

Chemistry, Technology
Although individuals and governments fall far short of maintaining Earth's pristine qualities, many do desire to minimize waste and its first cousin, pollution. Although one admirable action would be to minimize production, another is to recycle the resultant wastes. The late 19th and early 20th centuries introduced industrialization, and with it mechanization. Part of the mechanization was the automobile. And part of the automobile was the automobile tire. Tires are constructed of rubber or rubber-related products. They wear out well before most automobiles wear out. The problem is: what to do with all those worn-out, used tires? Millions and millions of them. They do not readily break down on being exposed to the elements. How can they be recycled? One Problem with Tires Now What might happen if tires were…
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Gutta Percha: From Underwater Cables to Golf Balls to Dental Work

Chemistry, History
[caption id="attachment_24465" align="alignright" width="340"] From the 1851 book: Gutta Percha, Its Discovery, History, and Manifold Uses[/caption] Gutta percha thermoplastic1 is a tough and leathery resinous produced from the milky fluid tapped from certain trees. Isoprene is an extremely important building block widespread in nature. The main component of gutta percha is, in fact, the trans-1,4-isomer of polyisoprene. The cis-1,4,-isomer is, interestingly enough, the primary constituent of natural rubber. It is produced from the milky fluid tapped from "other" trees. The reason for the considerable difference in physical characteristics between rubber and gutta percha (or, rather the trans and cis isomers of polypropylene) is the greater crystalline character of the trans isomer. Notice the difference between the trans and cis isomers in Image 2. How do these isomers differ? Synthesis from…
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Terpenes and Terpenoids: Isoprene Rule

There are thousands of chemical compounds in nature. They are divvied up into categories or classifications. These include hormones, alkaloids, vitamins, neurotransmitters, enzymes, proteins, and nucleic acids. One group of chemicals follows a structure rule called the isoprene rule. Many every day substances are part of this group. One example is turpentine. Another is beta-carotene (the source of the orange color in carrots). Chemicals such as these derived from isoprene are called terpenoids. Structure and Statement of the Isoprene Rule Isoprene consists of carbon and hydrogen. But it is not limited to single bonds. See the image of isoprene (C5H8) featured with this article. The double lines stand for double bonds. Since the carbon pairs involved have two bonds rather than one, a hydrogen atom is missing from each of them.…
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