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What does the initial DABCO after a Chiropractor's name mean?
"The American Board of Chiropractic Orthopedics (ABCO) is a voluntary, non-profit, professional credentialing board that certifies qualified chiropractic physicians and practitioners engaged in the field of chiropractic medicine who have met the professional knowledge standards established by the Board."
What are synonyms for the chemical name N N N' N'-Tetramethylethylenediamine?
CAS No.110-18-9Chemical Name:N,N,N',N'-TetramethylethylenediamineSynonyms:TD;TMED;TEMED;TMEDA;Tetrameen;propamined;Toyocat TE;Propamine D;Dabco TMEDA;Kaolizer 11CBNumber:CB2446761Molecular Formula:C6H16N2Formula Weight:116.2MOL File:110-18-9.molSee the Chemical Book
What is two-component polyurethane?
All polyurethane contains two chemicals: a diol and a diisocyanate. (There's also a catalyst called DABCO and a few other items in there to modify the finished polymer, but for now let's stick with the two important ones.) A two-component polyurethane brings you the diol and the diisocyanate as two separate packages. There are a couple of two-component systems available to someone who doesn't own a plastics plant: car paint, where you put hardener in the paint to make it dry, and sprayed foam insulation. The way most of us get our polyurethane is as single-component systems, because diisocyanate is very poisonous. Polyurethane varnish, Gorilla Glue, and polyurethane construction adhesive all work the same way: the diisocyanate is missing parts. If you add water to it--whether through the air or by moistening the surface--the diisocyanate picks up what it needs and the urethane reaction commences.
What are the basic chemicals in foam?
You mean like foam rubber and not the foam on a latte, correct? Foam rubber is actually "polyurethane foam" today; they don't make it out of rubber anymore. And when making polyurethane foam, four chemicals are needed. The first is a polymer polyol. Any chemical that ends in -ol is an alcohol; a polyol has "multiple" (read: hundreds) of hydroxyl groups per molecule. As you'd pretty much figured, these are huge molecules. The second is 1,4-diazabicyclo[2.2.2]octane. People call it "dabco," and with good reason. I mean, look at the name of this stuff! This is your catalyst. The third is a diisocyanate. There are two. In the OLD days everyone used toluene diisocyanate. TDI is extremely hazardous so polymer engineers are using more diphenylmethane diisocyanate, which isn't quite as hazardous. The important thing to know about diisocyanates is they are dangerous all the time: they are made out of a chemical warfare agent (specifically, a blood agent) called phosgene, and if heated too much turn into a different blood agent called hydrogen cyanide. Phosgene is so dangerous they're not allowed to transport it even across the street; it must be made at the same factory as the isocyanates. And every company that makes this stuff has to be registered as a chemical warfare agent factory with the United Nations. The fourth is a blowing agent, which makes it foam up. The first blowing agent, and one still used sometimes, is water. They found out about this by accident: Otto Bayer, who invented polyurethane and was not related to the Bayer family who started the chemical company, got some water into a batch of polyurethane that he was reacting out and was surprised as could be when it turned into foam rubber. Further research proved that adding water to diisocyanate releases carbon dioxide. Carbon dioxide gas is another popular blowing agent.
Can Polyurethane foam be used for home insulation?
Had my chem teacher in highschool grow the PU foam in front of the class, how did he do it? You need four chemicals: A polyol. For foam, glycerin will work. A diisocyanate. A catalyst called DABCO, which has a REALLY long name. And a blowing agent; for this we'll use water. There are two reactions going on here. First is the urethane reaction--DABCO bonds the polyol to the diisocyanate to form the urethane molecule. Then comes the water...when diisocyanate and water are mixed, carbon dioxide is liberated. The little CO2 bubbles are trapped in the polyurethane and make it foamy.
